ANKLAM v. SECRETARY OF HEALTH AND HUMAN SERVICES ( 2023 )


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  •        In the United States Court of Federal Claims
    OFFICE OF SPECIAL MASTERS
    Filed: November 29, 2023
    *************************
    BRIAN ANKLAM and KAREN ANKLAM, *
    as the legal representatives of the estate of *
    their daughter, N.A., deceased,               *      PUBLISHED
    *
    Petitioners,          *      No. 17-2061V
    *
    v.                                            *      Special Master Nora Beth Dorsey
    *
    SECRETARY OF HEALTH                           *      Dismissal; Measles, Mumps, Rubella,
    AND HUMAN SERVICES,                           *      Varicella (“MMRV”) Vaccine; Seizure;
    *      Death.
    Respondent.           *
    *
    *************************
    Curtis R. Webb, Monmouth, OR, for Petitioners.
    Katherine Carr Esposito, U.S. Department of Justice, Washington, DC, for Respondent.
    DECISION 1
    I.     INTRODUCTION
    On December 29, 2017, Brian Anklam and Karen Anklam (“Petitioners”), as legal
    representatives of the estate of their daughter, N.A., deceased, filed a petition for compensation
    under the National Vaccine Injury Compensation Program (“Vaccine Act” or “the Program”), 42
    1
    Because this Decision contains a reasoned explanation for the action in this case, the
    undersigned is required to post it on the United States Court of Federal Claims’ website and/or at
    https://www.govinfo.gov/app/collection/uscourts/national/cofc in accordance with the E-
    Government Act of 2002. 
    44 U.S.C. § 3501
     note (2018) (Federal Management and Promotion of
    Electronic Government Services). This means the Decision will be available to anyone with
    access to the Internet. In accordance with Vaccine Rule 18(b), Petitioners have 14 days to
    identify and move to redact medical or other information, the disclosure of which would
    constitute an unwarranted invasion of privacy. If, upon review, the undersigned agrees that the
    identified material fits within this definition, the undersigned will redact such material from
    public access.
    U.S.C. § 300aa-10 et seq. (2018). 2 Petitioners alleged that as a result of a Measles, Mumps,
    Rubella, Varicella (“MMRV”) vaccine N.A. received on June 23, 2016, N.A. developed a fever,
    which triggered a seizure that caused her death. 3 Petition at 2-3 (ECF No. 1). Respondent
    argued against compensation, stating that “this case is not appropriate for compensation under
    the terms of the [Vaccine] Act.” Respondent’s Report (“Resp. Rept.”) at 2 (ECF No. 9).
    After carefully analyzing and weighing the evidence presented in this case in accordance
    with the applicable legal standards, the undersigned finds that Petitioners have failed to provide
    preponderant evidence that N.A.’s MMRV vaccine caused her death. Thus, Petitioners have
    failed to satisfy their burden of proof under Althen v. Secretary of Health & Human Services,
    
    418 F.3d 1274
    , 1280 (Fed. Cir. 2005). Accordingly, the petition must be dismissed.
    II.    ISSUES TO BE DECIDED
    There are two factual disputes. Joint Prehearing Submission, filed June 3, 2022, at 4
    (ECF No. 72). The parties dispute whether N.A. suffered a seizure during the night of June 30,
    2016 or the morning of July 1, 2016. 
    Id.
     The parties also dispute whether N.A.’s autopsy slides
    show abnormalities in the hippocampus, 4 specifically granule cell dispersion and/or bilamination
    of the dentate gyrus. 5 
    Id.
    Regarding causation, the parties agree the Court should apply Althen but disagree as to
    whether Petitioners have provided preponderant evidence of the Althen prongs. Joint Prehearing
    Submission at 4-5. The parties agree the MMRV vaccine can cause febrile seizures and that
    2
    The National Vaccine Injury Compensation Program is set forth in Part 2 of the National
    Childhood Vaccine Injury Act of 1986, 
    Pub. L. No. 99-660, 100
     Stat. 3755, codified as amended,
    42 U.S.C. §§ 300aa-10 to -34 (2018) (“Vaccine Act” or “the Act”). All citations in this Decision
    to individual sections of the Vaccine Act are to 42 U.S.C.A. § 300aa.
    3
    N.A. also received Haemophilus influenzae type B (“Hib”), pneumococcal conjugate
    (“Prevnar”), and Hepatitis A vaccines on June 23, 2016; however, Petitioners allege only the
    MMRV vaccine caused N.A.’s death. Petition at 2-3; Joint Prehearing Submission, filed June 3,
    2022, at 4 (ECF No. 72).
    4
    The hippocampus is “a convoluted elevation of gray matter extending the entire length of the
    floor of the temporal horn of the lateral ventricle; it is part of the limbic system and plays major
    roles in short-term memory and spatial navigation.” Hippocampus, Dorland’s Med. Dictionary
    Online, https://www.dorlandsonline.com/dorland/definition?id=22696 (last visited Nov. 13,
    2023). Hippocampus is used “to denote the entire structure, including the hippocampus proper
    (Ammon’s horn), the dentate gyrus, and the subicular complex (presubiculum, parasubiculum,
    and subiculum), but it can also be used more restrictively, most often denoting the hippocampus
    proper, in which case the entire structure may be called the hippocampal formation.” Id.
    5
    Although not mentioned in the Joint Prehearing Submission, Petitioners’ expert, Dr. Miller,
    also opined that there was an abnormality in the medulla. See Petitioners’ Exhibit (“Pet. Ex.”)
    22 at 5, 8; Pet. Ex. 65 at 3; Transcript (“Tr.”) 23, 46-49.
    2
    most of these seizures occur between seven to 10 days after MMRV vaccination. Id. at 4.
    However, they disagree as to (1) whether the MMRV vaccination administered to N.A. on June
    23, 2016 caused her to have a vaccine-related seizure that led to her death, (2) whether an
    unobserved febrile seizure can cause a child to die, and (3) whether an unobserved febrile seizure
    did cause N.A. to die. Id.
    III.   BACKGROUND
    A.      Procedural History
    Petitioners filed a petition along with medical records on December 29, 2017. Petition;
    Petitioners’ Exhibits (“Pet. Exs.”) 1-8. Petitioners filed medical literature on March 29, 2018.
    Pet. Exs. 9-12. Respondent filed his Rule 4(c) Report on May 25, 2018, arguing against
    compensation. Resp. Rept. at 2.
    Petitioners filed an expert report from Dr. Marcel Kinsbourne on November 13, 2018 and
    an expert report from Dr. Douglas C. Miller on January 14, 2019. Pet. Exs. 13, 22. On May 30,
    2019, Respondent filed expert reports from Dr. Christine McCusker, Dr. Sara O. Vargas, and Dr.
    Hart G.W. Lidov. Resp. Exs. A, C, E. Petitioners filed supplemental expert reports from Dr.
    Kinsbourne and Dr. Miller and photomicrographs of autopsy slides on November 4, 2019. Pet.
    Exs. 61, 65-66. From February to June 2020, Respondent filed supplemental expert reports from
    Dr. McCusker, Dr. Lidov, and Dr. Vargas. Resp. Exs. H-J.
    The undersigned held a Rule 5 conference on August 18, 2020. Rule 5 Order dated Aug.
    19, 2020 (ECF No. 53). Prior to the conference, the parties filed briefs. Resp. Pre-Rule 5
    Conference Brief, filed Aug. 7, 2020 (ECF No. 51); Pet. Memorandum in Support of Rule 5
    Ruling Favoring the Petitioners, filed Aug. 7, 2020 (ECF No. 52). The undersigned
    preliminarily found Petitioners’ theory under Althen prong one may not be sound and reliable.
    Rule 5 Order at 1-2. The undersigned also preliminarily found no evidence that N.A. more likely
    than not suffered a seizure, and thus, given the lack of factual evidence and competing expert
    opinions, the undersigned was unable to conclude by preponderant evidence that N.A.’s
    hippocampus was pathologically abnormal. Id. at 2. As for the third Althen prong, the
    undersigned preliminarily found there was a temporal association but stressed that a temporal
    association alone is insufficient to prove causation. Id. Petitioners indicated their preference for
    an entitlement hearing, and one was set for January 2022. Id. at 2; Pre-Hearing Order dated
    Sept. 18, 2020 (ECF No. 55).
    On September 20, 2021, Respondent filed additional medical literature. Resp. Exs. K-L.
    On November 24, 2021, Petitioners filed their pre-hearing submissions along with an expert
    report and medical literature from Dr. Miller and a case review report from Sudden Unexplained
    Death in Childhood (“SUDC”) Registry and Research Collaborative (“SUDCRRC”). Pet.
    Prehearing Brief, filed Nov. 24, 2021 (ECF No. 58); Pet. Exs. 69-77. The undersigned held a
    status conference on December 9, 2021, on Respondent’s request, due to Petitioners’ recently
    filed expert report. Order dated Dec. 10, 2021 (ECF No. 64). Because Respondent’s experts
    were unable to prepare responsive expert reports prior to the hearing, and because Petitioners
    3
    preferred to receive these reports prior to the hearing, the entitlement hearing was moved to July
    2022. Id. at 1-2; Order dated Dec. 16, 2021 (ECF No. 66).
    Respondent filed supplemental expert reports from Dr. Lidov and Dr. Vargas on February
    28, 2022. Resp. Exs. M-N. Petitioners filed the parties’ joint submission on June 3, 2022, and
    Respondent filed his pre-hearing submission on June 7, 2022. Joint Prehearing Submission;
    Resp. Pre-Hearing Submission, filed June 7, 2022 (ECF No. 73).
    An entitlement hearing was held on July 12 and 13, 2022. Order dated July 14, 2022
    (ECF No. 75); Transcript (“Tr.”) 1, 219. Karen Anklam (N.A.’s mother), Dr. Miller, Dr.
    Kinsbourne, Dr. Lidov, Dr. Vargas, and Dr. McCusker testified. Tr. 3. Thereafter, additional
    medical literature and medical records were filed by the parties. Resp. Exs. U-Y; Pet. Exs. 78-
    80. In December 2022, Petitioners filed a post-hearing brief along with an affidavit from Mrs.
    Anklam, N.A.’s mother. Pet. Post-Hearing Brief, filed Dec. 13, 2022 (ECF No. 88); Pet. Ex. 81.
    On February 8, 2023, Respondent filed his post-hearing brief. Resp. Post-Hearing Brief, filed
    Feb. 8, 2023 (ECF No. 90). Petitioners filed a reply on March 13, 2023, and Respondent filed a
    sur-reply on April 4, 2023. Pet. Reply Brief, filed Mar. 13, 2023 (ECF No. 93); Resp. Sur-
    Reply, filed Apr. 4, 2023 (ECF No. 95).
    This matter is now ripe for adjudication.
    B.      Factual History
    1.      Stipulated Facts
    The parties agreed to the following stipulated facts as set forth in their Joint Prehearing
    Submission. See Joint Prehearing Submission at 1-4.
    N.A. was born on June 18, 2015 in Saginaw, Michigan. Pet. Ex. 2 at 3. She was noted to
    be doing well with appropriate growth and development at her one-year well-child visit on June
    23, 2016. Pet. Ex. 4 at 33. N.A. received Haemophilus influenzae type B (“Hib”),
    pneumococcal conjugate (“Prevnar”), Hepatitis A, and MMRV vaccinations on June 23, 2016 at
    the office of her pediatrician in Croswell, Michigan. Pet. Ex. 4 at 34.
    N.A.’s parents took N.A. and her three siblings to a splash park for about two hours
    during the afternoon of June 30, 2016. Pet. Ex. 1 at 2; Pet. Ex. 5 at 5. N.A.’s mother thought
    that N.A. had developed a fever at about 6:00 p.m. on the evening of June 30, 2016. Pet. Ex. 1 at
    3; Pet. Ex. 5 at 5. N.A.’s mother gave N.A. a 3.75 ml dose of Motrin and a tepid bath at about
    6:00 p.m. Pet. Ex. 1 at 3; Pet. Ex. 5 at 5. N.A.’s mother put N.A. in her crib for the night at
    between 6:30 p.m. and 7:00 p.m. on June 30, 2016. Pet. Ex. 1 at 3; Pet. Ex. 5 at 5.
    N.A. was found dead, face down in her crib, by her father, at about 9:00 a.m. on July 1,
    2016. Pet. Ex. 1 at 3; Pet. Ex. 5 at 2, 5; Pet. Ex. 6 at 1. He reported that he first saw N.A.’s feet
    sticking out of the crib slats. Pet. Ex. 1 at 3; Pet. Ex. 5 at 3. He said that N.A.’s feet were
    purple, her arms were straight out at her elbows at her sides (like a star), and her face was
    4
    straight down to the mattress. Pet. Ex. 1 at 3; Pet. Ex. 5 at 3-5. He did not see anything coming
    out of N.A.’s mouth. Pet. Ex. 1 at 3.
    N.A.’s father is an experienced paramedic. He immediately knew that N.A. was dead
    and had died some time before. Pet. Ex. 1 at 3; Pet. Ex. 5 at 5.
    An autopsy of N.A. was done on July 3, 2016. Dr. Kanu Virani, M.D., the Forensic
    Pathologist who performed the autopsy, opined
    [N.A.] died of asphyxia. She was found dead face down in a crib. The
    entire autopsy failed to identify any natural disease. Children at age of one year
    and older should be able to turn side way or face up at the time of possible
    breathing difficulties during sleep. The entire autopsy and investigation
    surrounding her death[] failed to identify [a] possible factor for asphyxia. There
    are no physical injuries. The manner of death is undeterminable.
    Pet. Ex. 6 at 1.
    Other potentially relevant notations in the autopsy report include Dr. Virani’s
    observations of a “[s]mall amount of mucus [] present in nostrils,” that the “[t]he respiratory
    mucosa [was] mildly congested,” a “[s]mall amount of mucus [] present in the trachea and
    bronchi,” and that “[t]here [was] no laryngeal edema or upper airway obstruction.” Pet. Ex. 6 at
    2-3. Microscopic examination of the lungs showed congested septa and minimal chronic
    inflammation of the submucosa of the epiglottis. Id. at 4.
    N.A.’s twin sister, L.A., slept in a separate crib in the same room as her sister. She also
    received an MMRV vaccination on June 23, 2016. During the evening of July 1, 2016, Mrs.
    Anklam noted that L.A. had a rash on her back and felt a little warm. She had an elevated
    temperature, less than 100°F. Pet. Ex. 1 at 4. Petitioners brought L.A. to the emergency room
    (“ER”) at the local hospital on July 1, 2016. She had a temperature of 100.2°F (rectal) at the
    hospital. Pet. Ex. 1 at 4; Pet. Ex. 7 at 3.
    N.A.’s older brother, L.B.A. (DOB: 04/25/2012), experienced febrile seizures on March
    16, 2015, and August 28, 2016, and was seen in the hospital on July 17, 2016, for fever,
    vomiting, and being “somewhat dazed and not acting quite right.” Pet. Ex. 1 at 4; Pet. Ex. 7 at 4-
    6, 9-14, 24-27.
    2.   Summary of Medical Records
    In addition to the facts stipulated to by the parties, the following summary of facts
    provides additional relevant information.
    N.A. was born on June 18, 2015, along with her twin sister, L.A., without complications.
    Pet. Ex. 2 at 3. N.A. had a heart murmur that was resolved by discharge on June 21, 2015. Pet.
    Ex. 3 at 6-8; Pet. Ex. 4 at 2. At discharge, N.A. had a normal examination and appeared healthy.
    Pet. Ex. 3 at 6-8.
    5
    N.A. visited her pediatrician, Dr. Matthew Gormley, regularly for well-child visits from
    June 2015 to March 2016. Pet. Ex. 4 at 2-17, 20-27. N.A. was noted to be doing well and had
    appropriate growth and development. Id. at 3, 7, 12, 15-16, 21-22, 26. At visits in September
    2015 and November 2015, N.A. received Pediatrix (diphtheria-tetanus-acellular pertussis
    (“DTaP”), hepatitis B, and Polio), Hib, Rotarix (Rotavirus), and Prevnar vaccinations. Id. at 12,
    16. N.A. received the third doses of Pediatrix and Prevnar at a visit in December 2015. Id. at 22.
    No adverse reactions were noted following these vaccinations. See id. at 12, 16, 22.
    On November 23, 2015, N.A. presented to Dr. Gormley with “nasal congestion and
    cough/wheezing for the last [three] weeks.” Pet. Ex. 4 at 18. She had no fever or chills. Id.
    Assessment was an upper respiratory infection. Id. Dr. Gormley noted it was likely a viral
    illness and recommended follow-up if no improvement. Id.
    N.A. presented to Dr. Gormley’s office on May 13, 2016. Pet. Ex. 4 at 28. N.A. had
    some congestion, slight swelling near the right eye, and some eye drainage the day prior. Id. By
    that morning, the right eye was red and swollen shut. Id. No fever was noted. Id. Assessment
    was cellulitis. Id. N.A. was prescribed Cephalexin and was directed to return in one week. Id.
    On May 18, 2015, N.A. returned for a follow-up examination. Pet. Ex. 4 at 30. N.A.’s
    father reported her “eye [was] no longer red or swollen and [there was] no further drainage.” Id.
    N.A. was tolerating the antibiotics well. Id. Physical examination was normal. Id. N.A. was
    noted to have a body mass index in the “5th percentile to less than 85th percentile for age.” Id.
    Notes indicated N.A.’s cellulitis was “resolved.” Id. N.A.’s parents were instructed to continue
    giving her Cephalexin twice daily. Id.
    N.A. presented to Dr. Gormley for her one-year well-child visit on June 23, 2016. Pet.
    Ex. 4 at 32. She was not currently on any medications. Id. N.A. did not have a fever, cough, or
    breathing issues. Id. Physical examination was normal. Id. at 33. Dr. Gormley noted N.A. was
    “[d]oing well” and had “appropriate growth and development.” Id. At this visit, N.A. received
    her third Hib, fourth Prevnar, first hepatitis A, and first MMRV vaccinations. Id. at 34. No
    adverse reactions were noted. See id. at 32-35.
    On the morning of July 1, 2016, shortly after 9:00 a.m., N.A. was found unresponsive in
    her crib. Pet. Ex. 5 at 3. N.A. “had obvious rigor mortis and was cold to the touch.” Id. at 3.
    She “also had pooling on her skin that indicated that she had been deceased for some time.” Id.
    Time of death was placed between 9:00 p.m. and 10:00 p.m. on June 30, 2016. Id. at 6.
    3.     Sheriff’s Records
    The Sheriff’s records indicated Officer Robby Joe Wendling arrived on scene at
    approximately 9:35 a.m. on July 1, 2016. Pet. Ex. 5 at 3. He entered N.A.’s room and noted she
    was face up, “had obvious rigor mortis[,] and was cold to the touch.” Id. She “also had pooling
    on her skin that indicated that she had been deceased for some time.” Id.
    6
    Detective Mark Ruggles and Sergeant Shelly Park arrived on the scene shortly thereafter.
    Pet. Ex. 5 at 4. Detective Ruggles noted rigor mortis was fixed, livor mortis was consistent with
    Mr. Anklam’s description that N.A. was found face down in a blanket, and N.A. was cold to the
    touch. Id. Detective Ruggles examined N.A. and found no injuries. Id.
    The Incident Report documented that Petitioners took their children, including N.A., to
    the Splash Pond until 5:15 p.m. on June 30, 2016. Pet. Ex. 5 at 5. Once the family arrived
    home, the children were fed chicken noodle soup for dinner and then given a bath. Id. Mrs.
    Anklam stated N.A. was running a low-grade fever and given Motrin around 6:00 p.m. Id.
    Around 6:30 p.m., the children were put to bed. Id. Petitioners reported they did not hear
    anything from L.A. and N.A.’s room during the night. Id.
    Mrs. Anklam stated she woke up around 6:30 a.m. and did not check on N.A. prior to
    leaving for work. Pet. Ex. 5 at 5. Mr. Anklam stated he went into L.A. and N.A.’s room around
    9:00 a.m., when he found L.A. awake. Id. While changing L.A.’s diaper, he noticed N.A.’s
    “feet were just outside the rails of the crib.” Id. He noticed “some discoloring to [N.A.’s] feet”
    and felt they were cold. Id. He turned her over and saw “she was ‘pooling.’” Id. “[Mr.
    Anklam] stated that he knew right away that she was dead.” Id.
    Petitioners reported that N.A. “ha[d] been running a low grade fever, sometimes up to
    100.5 since [June 19, 2016].” Pet. Ex. 5 at 5. The fever would fluctuate and sometimes
    dissipate. Id. Other than that, N.A.’s only other issue since birth was right eye swelling in May
    2016. Id.
    Time of death was placed between 9:00 p.m. and 10:00 p.m. on June 30, 2016. Pet. Ex. 5
    at 6.
    4.      Autopsy 6
    An autopsy was conducted by Dr. Virani on July 3, 2016. Pet. Ex. 6 at 1. Autopsy
    findings indicated asphyxia with pulmonary edema and blanching on face. Id. Dr. Virani opined
    [N.A.] died of asphyxia. She was found dead face down in a crib. The
    entire autopsy failed to identify any natural disease. Children at age of one year
    and older should be able to turn side way or face up at the time of possible
    breathing difficulties during sleep. The entire autopsy and investigation
    surrounding her death[] failed to identify [a] possible factor for asphyxia. There
    are no physical injuries. The manner of death is undeterminable.
    Id.
    External examination noted “[b]lanching . . . in central portion of the face” and “[s]mall
    amount of mucus present in nostrils.” Pet. Ex. 6 at 2. Internal examination revealed the
    “hippocampi [were] without abnormality.” Id. There was no abnormality of the head or brain.
    6
    For additional facts and findings found during the autopsy, see Pet. Ex. 6.
    7
    Id. “There [was] no laryngeal edema or upper airway obstruction.” Id. at 3. Examination of the
    respiratory system revealed “[p]ulmonary edema and congestion,” “[s]mall amount of mucus . . .
    in trachea and bronchi,” and “mildly congested” respiratory mucosa. Id.
    Microscopic examination of the lungs revealed “edema fluid and scatter macrophages[7]
    in alveoli,” 8 congested septa, 9 and “[m]inimal chronic inflammation . . . in the submucosa of
    epiglottis.” Pet. Ex. 6 at 4. There was no acute or chronic inflammation in the trachea or
    bronchi and no evidence of aspirated foreign material and inflammation in airways or alveoli.
    Id.
    Dr. Virani examined sections of the brain and did not find any abnormality. Pet. Ex. 6 at
    4. He also reviewed “[s]ections of brain, heart, liver, spleen, thymus, kidneys, thyroid, adrenals,
    pituitary, stomach, intestines, appendix, pancreas, lymph nodes, bone marrow[,] and urinary
    bladder” and reported that they were all “unremarkable.” Id. Additionally, toxicology testing
    did not reveal any positive findings. Id. at 5-6.
    Dr. Virani documented the date of death to be “June 30, 2016, unknown PM.” Pet. Ex. 6
    at 1.
    7
    A macrophage is a “form[] of mononuclear phagocytes found in tissues” that “arise from
    hematopoietic stem cells in the bone marrow.” Macrophage, Dorland’s Med. Dictionary Online,
    https://www.dorlandsonline.com/dorland/definition?id=29296 (last visited Nov. 13, 2023).
    Macrophages engage in “[p]hagocytic activity” and are also “involved in cell-mediated immune
    responses.” Stedman’s Medical Dictionary 1141 (28th ed. 2006). Phagocytosis is the process by
    which “particulate material, such as microorganisms or cell fragments[,] . . . is taken into the cell
    in membrane-bound vesicles (phagosomes) that originate as pinched-off invaginations of the
    plasma membrane. Phagosomes fuse with lysosomes, forming phagolysosomes in which the
    engulfed material is killed and digested.” Phagocytosis, Dorland’s Med. Dictionary Online,
    https://www.dorlandsonline.com/dorland/definition?id=38307 (last visited Nov. 13, 2023).
    8
    An alveolar macrophage is “a rounded granular type, found within the alveoli of the lungs and
    serv[es] to ingest inhaled particulate matter.” Alveolar Macrophage, Dorland’s Med. Dictionary
    Online, https://www.dorlandsonline.com/dorland/definition?id=87677 (last visited Nov. 13,
    2023). Alveolus is “a small saclike structure” found in the lungs. Alveolus, Dorland’s Med.
    Dictionary Online, https://www.dorlandsonline.com/dorland/definition?id=2006 (last visited
    Nov. 13, 2023).
    9
    Septum is “a dividing wall or partition.” Septum, Dorland’s Med. Dictionary Online,
    https://www.dorlandsonline.com/dorland/definition?id=45434 (last visited Nov. 13, 2023).
    Septa can “separate adjacent pulmonary alveoli, containing connective tissue constituents of the
    respiratory tissue and the capillary network of the blood supply of the lung.” Interalveolar
    Septum, Dorland’s Med. Dictionary Online, https://www.dorlandsonline.com/dorland/definition?
    id=105585 (last visited Nov. 13, 2023).
    8
    5.     SUDC Registry and Research Collaborative Case Review Report
    Petitioners participated in the SUDCRRC, consenting to have N.A.’s case reviewed. This
    collaborative “analyzes cases of sudden unexpected deaths in children to understand risk factors
    and causes and to develop preventative measures by studying available records . . . and
    performing genetic analyses and special studies.” Pet. Ex. 77 at 3.
    As part of the case review, N.A.’s parents were interviewed. In the interview on
    September 1, 2016, N.A.’s parents (Petitioners) reported no concerns about N.A.’s development.
    Pet. Ex. 77 at 5. During her life, N.A. had “no known seizures.” Id. During the last 48 hours of
    her life, N.A. was “[c]ongested occasionally, but otherwise fine.” Id. In her last 24 hours, N.A.
    “had a minor cold and [] appeared ‘worn out, but not lethargic.’” Id. She also had a low-grade
    fever. Id. She was given one dose of Motrin after her dinner at 6:00 p.m. Id. at 5, 8.
    Autopsy tissue of the brain (3 slides) was reviewed by the SUDCRRC neuropathologist
    who found no significant histopathology. Pet. Ex. 77 at 8. Further, “[t]he SUDCRRC Forensic
    Pathology reviewers were in complete agreement with the reviews of the study’s . . .
    neuropathologist.” Id. Based on their review, the “forensic pathologist consider[ed] the
    significant findings . . . to be: 1) [s]ibling with genetic syndrome associated with slightly
    prolonged QT,[10] 2) [s]ibling with febrile seizures, 3) [f]ound prone with face pressed into
    mattress with blanching lividity on face.” Id. at 8-9. Under cause of death, the report concluded
    N.A.’s death was an “[u]nexplained sudden death,” with intrinsic factors including “[f]ebrile at
    time of death and evidence of immune activation” and extrinsic factors including “[f]ound prone
    with face down with blanching.” Id. at 9. The manner of death was “[u]ndetermined.” Id. The
    report was signed by Dr. Orrin Devinsky, Principle Investigator. Id. at 10.
    A SUDCRRC genetic panel was also performed for N.A. and “[n]o clinically significant
    variants [were] identified.” Pet. Ex. 80 at 2.
    6.     Mrs. Anklam’s Affidavit & Hearing Testimony
    Mrs. Anklam is N.A.’s mother. Tr. 6; Pet. Ex. 1 at ¶ 1. She works as a nurse anesthetist,
    and her husband, Mr. Anklam, is a paramedic. Tr. 225; Pet. Ex. 1 at ¶¶ 19, 33.
    N.A. was born on June 18, 2015. Pet. Ex. 1 at ¶ 2. She had a heart murmur that resolved
    prior to discharge. Id. “[N.A.] was healthy and developing normally until her sudden death on
    June 30, 2016.” Id. at ¶ 3. Her “development was normal” and she was “always fed well.” Id.
    at ¶¶ 4-5.
    10
    “A prolonged QT interval is an irregular heart rhythm that can be seen on an
    electrocardiogram. It reflects a disturbance in how the heart’s bottom chambers (ventricles) send
    signals. In a prolonged QT interval, it takes longer than usual for the heart to recharge between
    beats.” Prolonged QT Interval, Mayo Clinic, https://www.mayoclinic.org/diseases-
    conditions/long-qt-syndrome/multimedia/prolonged-q-t-interval/img-20007972 (last visited Nov.
    13, 2023).
    9
    On June 23, 2016, N.A. received her third Hib, fourth Prevnar, first hepatitis A, and first
    MMRV vaccinations at the office of her pediatrician, Dr. Gromley. Pet. Ex. 1 at ¶ 6. Although
    she cried after receiving the vaccinations, her “behavior was pretty normal.” Id. at ¶¶ 7-8. For
    the first two days following the vaccinations, Mrs. Anklam gave N.A. Motrin. Id. at ¶ 8.
    Because she was getting her first molars, “she was a little more cranky and drooling more than
    usual.” Id. “[N.A’s] behavior was unremarkable from June 23 to June 29.” Id. at ¶ 9.
    On the morning of June 30, 2016, N.A. was well. Tr. 6. That afternoon, around 3:00
    p.m., Petitioners took their children, including N.A., to a splash park. Tr. 6-7; Pet. Ex. 1 at ¶ 10.
    “[N.A.] was a bit crankier than usual, but it was a warm day, and [Mrs. Anklam] attributed it to
    that.” Pet. Ex. 1 at ¶ 10. They arrived home around 5:00 p.m. and had chicken noodle soup for
    dinner, which ended sometime between 5:30 p.m. and 5:45 p.m. Tr. 7, 14; Pet. Ex. 1 at ¶ 11.
    “N.A. was very sleepy.” Tr. 8; see also Pet. Ex. 1 at ¶ 11.
    Following dinner, both N.A. and her twin sister, L.A., felt warm. Tr. 8; Pet. Ex. 1 at ¶ 12.
    Because of her experience as a mother and a nurse, Mrs. Anklam did not take their temperatures.
    Tr. 8; Pet. Ex. 1 at ¶ 13. She bathed both N.A. and L.A. together and noted they were both fine
    at the time. Tr. 9. Following the bath, Mrs. Anklam gave both N.A. and L.A. Motrin around
    6:30 p.m., before putting them to bed in the same room in separate cribs sometime between 7:00
    p.m. and 7:30 p.m. Tr. 9-10, 14; Pet. Ex. 1 at ¶ 14.
    During the night, Petitioners did not hear anything from N.A.’s room. Pet. Ex. 1 at ¶ 15.
    N.A. and L.A. had been sleeping longer, and Petitioners attributed it to a growth spurt. Id. at ¶
    16.
    The following morning, July 1, 2016, Mrs. Anklam left home at 6:30 a.m. to go to work.
    Tr. 10. She did not check on N.A. and L.A. prior to leaving for work. Tr. 10-11. Mr. Anklam
    went into N.A. and L.A.’s room around 9:00 a.m. that morning. Pet. Ex. 1 at ¶ 17. “When he
    glanced at [N.A.’s] crib, he knew something was wrong. Her feet were sticking out of the crib
    slats and her arms were straight at the elbows and out to her sides (like a little star).” Id. at ¶ 18.
    He saw N.A.’s feet were purple, she was face down, and “[t]here was nothing coming out of her
    mouth.” Id. at ¶ 19. “He picked [N.A.] up and knew she was dead and had been for a while.”
    Id. at ¶ 20. He then called 911 and Mrs. Anklam. Id.
    Mrs. Anklam testified that she never saw N.A. have a seizure or knew her to have a fever
    in excess of 100°F. Tr. 15.
    Mrs. Anklam testified the none of the three other children were ill on June 30, 2016, or
    showed symptoms of infection on July 1, 2016. Tr. 12. However, during the evening of July 1,
    2016, around 7:00 p.m., Petitioners took N.A.’s twin sister L.A. to the ER because she had a
    slightly elevated fever and a rash on her back. Tr. 11; Pet. Ex. 1 at ¶¶ 21, 24. Mrs. Anklam
    averred that she was terrified to put her to bed because Petitioners did not know what led to
    N.A.’s death. Pet. Ex. 1 at ¶¶ 21-22. A thorough work up was completed and L.A. was
    discharged shortly after 9:00 p.m. Id. at ¶ 24.
    10
    After N.A. passed, Petitioners enrolled their family in a study of SUDC. Pet. Ex. 1 at ¶
    26. “Throughout [their] participation in that study []and [Mrs. Anklam’s] own efforts to
    understand [N.A.’s] death[], [she] [] learned medical literature links [SUDC] to unobserved
    febrile seizures,” which she averred “seem[s] especially relevant to [N.A.’s] death because
    MMRV vaccinations cause fevers and febrile seizures in the second week after vaccinations.”
    Id. at ¶¶ 27-28.
    Additionally, Mrs. Anklam explained that one of her sons had suffered three febrile
    seizures, and “[she] learned that children who die unexpectedly often have a history of febrile
    seizures or a family history of febrile seizures.” Pet. Ex. 1 at ¶¶ 28, 41. His first seizure
    occurred on March 16, 2015. Id. at ¶ 30; Tr. 14-15, 224. On that day, he complained of ear pain
    and he had a “high normal” temperature below 100°F. Tr. 224; Pet. Ex. 1 at ¶ 30. He was given
    Motrin. Tr. 224; Pet. Ex. 1 at ¶ 30. While at the park over one hour later, he began seizing. Tr.
    224-25; Pet. Ex. 1 at ¶¶ 31-32. When they arrived at the ER, his temperature was between 103°F
    and 104°F. Tr. 225; Pet. Ex. 1 at ¶ 35. He had two subsequent febrile seizures in July and
    August 2016. Pet. Ex. 1 at ¶¶ 36-40. He had genetic testing done that showed he had a 3q26
    microdeletion, which Mrs. Anklam testified is not associated with seizures. Tr. 16, 223.
    Additionally, following N.A.’s passing, the other three children received cardiac evaluations, and
    all three were cleared. Tr. 15.
    C.      Expert Reports
    1.      Petitioners’ Expert, Dr. Douglas C. Miller, M.D., Ph.D. 11
    a.      Background and Qualifications
    Dr. Miller is an anatomic pathologist and a neuropathologist. Tr. 18. He received his
    B.A. in biology from Williams College in Massachusetts and his M.D. and Ph.D. in physiology
    and biophysics from the University of Miami in Florida. Pet. Ex. 23 at 1. Thereafter, he
    completed an anatomic pathology residency and a neuropathology residency at Massachusetts
    General Hospital. Id. Dr. Miller has held various teaching and consulting positions throughout
    his career. Id. at 3-4. He currently works as a Professor in the Department of Pathology and
    Anatomical Sciences at the University of Missouri Medical Center, is the Chair of the
    Department of Pathology, and is the Director of the Pathology Residency Program. Tr. 18-19.
    He has authored or co-authored almost 300 publications. Pet. Ex. 23 at 7-27. Dr. Miller has
    served as a neuropathology consultant for medical examiners for over 30 years and he has
    “extensive experience with the neuropathology of sudden infant death.” Pet. Ex. 22 at 2-3.
    11
    Dr. Miller testified at the hearing and submitted three expert reports. Tr. 3; Pet. Exs. 22, 65,
    69. Some of Petitioners’ medical literature contains pagination that begins at page one, and
    others begin at varying page numbers. To avoid confusion, the undersigned used pagination
    consistent with the ECF pagination for the medical literature that did not begin at page one.
    11
    b.      Opinion 12
    Dr. Miller opined that the MMRV vaccination administered to N.A. on June 23, 2016 led
    to a fever on June 30, that provoked a seizure that night, which caused N.A.’s death. Tr. 21-22,
    25, 34-35.
    i.      Background
    Dr. Miller discussed the relevant syndromes, including sudden unexplained death in
    children (“SUDC”), sudden infant death syndrome (“SIDS”), and sudden unexplained death in
    epilepsy (“SUDEP”), and briefly explained their relevance to this case. He classified N.A.’s case
    as SUDC, or sudden unexplained death in a young child over the age of one year when “there is
    no identified underlying disease or cause of death, including after a thorough autopsy, to which
    death can be attributed, plus a detailed scene investigation which confirms that the environment .
    . . cannot be blamed for [the child’s] death.” Pet. Ex. 22 at 5; see also Tr. 42.
    He did not classify N.A.’s case as SIDS given her age at death 13 because SIDS “is
    defined as the sudden unexpected death of a child older than [one] month of age and no older
    than one year of age, for which no anatomic or toxicological cause of death can be found after a
    thorough scene investigation and thorough complete autopsy.” Pet. Ex. 22 at 5; see also Tr. 41-
    42. Dr. Miller noted, however, “such arbitrary limits” between SUDC and SIDS “have little
    scientific basis.” Pet. Ex. 22 at 5. Although N.A.’s autopsy did not conclude that she had SUDC
    or SIDS, he found these terms have bearing on N.A.’s cause of death because their risk factors,
    including sleeping position and fever, 14 are relevant to this case. Id. at 4; Tr. 42-43.
    Lastly, Dr. Miller did not classify N.A.’s case as SUDEP because she did not have
    epilepsy, which by definition, requires two unprovoked seizures separated in time. Tr. 45, 67.
    12
    At the hearing, Dr. Miller testified that his opinions in his first expert report regarding
    “vaccine adjuvants and cytokines . . . [are] not relevant to this case.” Tr. 61; see Pet. Ex. 22 at 9-
    12. He also retracted his opinions related to “the hypercarbia theory where there was a build-up
    of carbon dioxide.” Tr. 61; see Pet. Ex. 22 at 6-12. As such, the undersigned will not address
    these opinions.
    13
    At the hearing, and in his expert reports, Dr. Miller argued that N.A. was born slightly early at
    36 weeks and 3 days, and thus, her actual age at death could be calculated to be less than one
    year, which would make this a SIDS case. Pet. Ex. 22 at 5; Tr. 41-42. The undersigned does not
    find this opinion affects her opinions or is determinative, and therefore, she will not address it.
    14
    Dr. Miller acknowledged that vaccination is not a risk factor but noted that fever is a risk
    factor, and fevers are associated with vaccinations, including MMRV. Tr. 43. Dr. Miller was an
    expert in the Boatmon case, where the Federal Circuit held that mere evidence that it was
    “medically plausible” that the premature infant’s death was caused by vaccinations failed to
    demonstrate a causal connection required for compensation under the Vaccine Act. Boatmon v.
    Sec’y of Health & Hum. Servs., 
    941 F.3d 1351
     (Fed. Cir. 2019). In this case, Dr. Miller testified
    that he did not “plan on relitigating Boatmon . . . . That’s not what this case is about.” Tr. 43.
    12
    Dr. Miller agreed that there was no evidence that N.A. ever had another seizure, which he opined
    is common in SUDC cases. Tr. 43.
    ii.     Althen Prong One
    Dr. Miller opined the MMRV vaccine can lead to fever and febrile seizure, and a seizure
    can lead to death. Pet. Ex. 22 at 8. As an overview, Dr. Miller opined that a child who receives
    an MMRV vaccine has “a significant risk of fever and febrile seizures,” and “[s]uch seizures,
    occurring unwitnessed in sleep, would present a significant risk of death in a child with a
    dysplastic dentate gyrus (the hippocampal abnormality associated with SUDC), with or without
    defects in the medullary 5HT system (such as the abnormality in the accurate nuclei associated
    with SIDS).” 
    Id.
     He further opined that the risk of death is greater in a child with both defects.
    
    Id.
     He opined that “[t]his chain of events represents a highly plausible, scientifically valid,
    hypothesis.” 
    Id. at 13
    .
    He explained that the MMRV vaccine can lead to fevers and seizures seven to 10 days
    after vaccination. Pet. Ex. 22 at 8, 12; see Tr. 34, 39; Pet. Ex. 19 at 2; 15 Pet. Ex. 21 at 2, 4-5. 16
    “Fever is one of the consequences of the vaccination,” explained Dr. Miller, “and fever can
    predispose to seizures.” Tr. 34. He testified that “[a]ll people . . . have some risk . . . of having a
    febrile reaction to a vaccine.” 
    Id.
     For the MMRV vaccine in particular, Dr. Miller noted there is
    a “significantly greater risk of febrile seizures with a peak period of around seven to 10 days
    after the vaccination.” 
    Id.
     He acknowledged that such an event is “rare” but maintained that
    there is a “significantly increased risk” of fever and febrile seizures following the MMRV
    vaccine. Tr. 23-24, 58, 60.
    Dr. Miller then explained that febrile seizures “certainly can lead to death in a vulnerable
    patient.” Tr. 37. “Seizures represent an electrical storm . . . that affects the brain and leads to a
    number of other things that can happen.” 
    Id.
     For example, “electrical impulses from the
    cerebral hemispheres where the seizures occur[] can be transmitted down into the brainstem and
    the brainstem controls both respiratory effort and heart rate.” 
    Id.
     Thus, “a sudden electrical
    discharge can shut down the medulla and cause cessation of breathing and/or cardiac
    arrhythmia.” 
    Id.
     This “electrical activity may also stimulate an outpouring of autonomic
    nervous system activity,” which can lead to “a discharge of sympathetic [] neurons [that] can
    also lead to cardiac arrhythmia and death.” Tr. 37-38.
    15
    Nicola P. Klein et al., Safety of Measles-Containing Vaccines in 1-Year-Old Children, 135
    Pediatrics e321 (2015).
    16
    Shannon E. MacDonald et al., Risk of Febrile Seizures After First Dose of Measles-Mumps-
    Rubella-Varicella Vaccine: A Population-Based Cohort Study, 186 Canadian Med. Ass’n J. 824
    (2014).
    13
    Next, he discussed the significance of abnormalities in the hippocampal and medullary
    brain tissue in sudden and unexpected deaths of children. 17 Pet. Ex. 22 at 5-9. He stated that the
    literature shows “a significant association between finding [] dentate gyrus abnormalities in
    children who have died in sleep and found dead, usually in a prone position, and with no
    anatomic cause of the death.” Tr. 24-25. Literature has also “made an explicit connection []
    suggest[ing] these children died in sleep or emerging from sleep at a time when the brain is more
    vulnerable to epileptogenesis, especially when the dentate gyrus, which normally acts as a sort of
    electrical gate to tamp down neuronal activity in the hippocampus, is defective.” Pet. Ex. 65 at
    2. Additionally, children with “hippocampal abnormalities at autopsy either themselves had a
    previous febrile seizure or had a first- or second-degree relative who had a febrile seizure
    history,” and thus, Dr. Miller opined there is “an increased risk for this kind of sudden
    unexplained death when there’s a family history of febrile seizures.” Tr. 26, 33.
    He testified that the hippocampus is located in the temporal lobe, with one on each side
    or hemisphere of the brain. Tr. 22. “[I]t is a very important structure in formation and
    consolidation of memories, other kinds of structures which are generally referred to as part of the
    limbic system, . . . and is frequently associated with temporal lobe seizures.” Tr. 22-23; see, e.g.,
    Pet. Ex. 28 at 9, 11. 18
    Dr. Miller opined that a “finding frequently found in autopsies of children whose death is
    classified as SUDC, SIDS[,] and [SUDEP]” is “dentate gyrus dysplasia, with what is termed
    granule cell dispersion including bilamination.” Pet. Ex. 22 at 4-5 (internal quotations omitted)
    17
    At the hearing, Dr. Miller also maintained febrile seizures can be fatal, even without
    hippocampal abnormalities. Tr. 51, 54.
    18
    Marco M. Hefti et al., Hippocampal Malformation Associated with Sudden Death in Early
    Childhood: A Neuropathologic Study, 12 Forensic Sci. Med. & Pathology 14 (2016).
    14
    (citing Pet. Ex. 18; 19 Pet. Ex. 25; 20 Pet. Ex. 26; 21 Pet. Ex. 27; 22 Pet. Ex. 28; Pet. Ex. 29) 23 (noting
    this abnormality on autopsy “is believed to be related to an increased risk of seizures and sudden
    death related to seizures”); see also Tr. 69. The dentate gyrus is thought to govern nerve
    impulses in the hippocampus, and when it is dysplastic or abnormal, seizures may be generated.
    Pet. Ex. 69 at 2. Granule cell dispersion is an “abnormality of the gyrus in which some cells are
    located beyond the normal boundaries of that narrow line.” Pet. Ex. 65 at 1. Bilamination, a
    form of dispersion, “describes lines of such granular cells outside the normal boundaries of the
    gyrus parallel to the direction of the gyrus.” 24 
    Id. at 2
    .
    Also, according to Dr. Miller, a brain abnormality in the medullas of infants is seen in
    over 70% of SIDS cases. Pet. Ex. 22 at 5, 8; Pet. Ex. 65 at 3. These abnormalities “involv[e]
    one or more parts of a network of neurons utilizing serotonin (5HT) as a neurotransmitter.” Pet.
    Ex. 65 at 3 (citing, e.g., Pet. Ex. 67; 25 Pet. Ex. 68); 26 see also Pet. Ex. 22 at 5, 8. Dr. Miller
    explained that “[t]he neurons of this network have their developmental origins in cells from the
    embryonic rhombic lip, and so other abnormalities of rhombic-lip derived structures may suggest
    that there are abnormalities of the 5HT system, even though those specific abnormalities may not
    be detectable at autopsy except by special research techniques” not routinely availability in
    forensic autopsies. Pet. Ex. 65 at 3; see also Pet. Ex. 22 at 5, 8. “The inferior olivary nuclei are
    19
    Hannah C. Kinney et al., Sudden Death, Febrile Seizures, and Hippocampal and Temporal
    Lobe Maldevelopment in Toddlers: A New Entity, 12 Pediatric & Developmental Pathology 455
    (2009).
    20
    Michael L. Rodriguez et al., Hippocampal Asymmetry and Sudden Unexpected Death in
    Infancy: A Case Report, 8 Forensic Sci. Med. & Pathology 441 (2012).
    21
    Hannah C. Kinney et al., Dentate Gyrus Abnormalities in Sudden Unexplained Death in
    Infants: Morphological Marker of Underlying Brain Vulnerability, 129 Acta Neuropathologica
    65 (2015).
    22
    Marco M. Hefti et al., Sudden Unexpected Death in Early Childhood: General Observations in
    a Series of 151 Cases, 12 Forensic Sci. Med. & Pathology 4 (2016).
    23
    Hannah C. Kinney et al., Hippocampal Formation Maldevelopment and Sudden Unexpected
    Death Across the Pediatric Age Spectrum, 75 J. Neuropathology & Experimental Neurology 981
    (2016).
    24
    Citing an article from Dr. Kinney, Dr. Miller noted “the minimum number of cells to qualify
    for bilamination would be eight.” Tr. 31; see also Pet. Ex. 65 at 2. It is not clear from the record
    which article Dr. Miller was referring to.
    25
    Y. Ozawa & N. Okado, Alteration of Serotonergic Receptors in the Brain Stems of Hyman
    Patients with Respiratory Disorders, 33 Neuropediatrics 142 (2002).
    26
    Y. Ozawa & S. Takashima, Developmental Neurotransmitter Pathology in the Brainstem of
    Sudden Infant Death Syndrome: A Review and Sleep Position, 130S Forensic Sci. Int’l S53
    (2002).
    15
    also rhombic lip derivatives,” and thus, “the presence of the gaps in neuronal populations . . . are
    evidence of such medullary abnormalities.” Pet. Ex. 65 at 3.
    Dr. Miller testified that the mechanism at play in a SUDC case “may be similar or
    identical” to the mechanism purported in SUDEP, described in more detail below. Tr. 67-68.
    He also explained that the literature has reported three main commonalities in SUDC cases: (1)
    “the deceased young child[] ha[s] a high frequency of a family history of febrile seizures;” (2)
    the child is “almost always found dead in bed, in a prone position;” and (3) the autopsy discloses
    hippocampal dysplasia. Pet. Ex. 22 at 5; see also Pet. Ex. 65 at 2; Pet. Ex. 74. 27 For support, Dr.
    Miller discussed various articles from Kinney et al. and others who described abnormalities in
    the hippocampus that they associated with sudden unexpected death, fever, and a family history
    of febrile seizures. Pet. Ex. 65 at 2.
    In 2009, Kinney et al. examined 64 cases of sudden death in children aged one to 5.9
    years to determine whether SUDC “is characterized by hippocampal and temporal lobe
    maldevelopment and an individual and/or family history of simple febrile seizures.” Pet. Ex. 18
    at 1. In the 49 SUDC cases, 28% had a familial history of febrile seizures, 98% were found
    during sleep, and 79% were found in the prone sleep position. 
    Id. at 1
    , 10 tbl.1. Twenty-six of
    the 49 SUDC cases had hippocampal sections available for examination, and 16 of these cases
    (16/26 or 62%) had hippocampal abnormalities. 
    Id. at 5
    , 10 tbl.1. When compared to non-
    SUDC cases, Kinney et al. found SUDC cases had more hippocampal abnormalities (62% versus
    22%). 
    Id. at 5
    .
    Kinney et al. separated their data into three groups—SUDC with a personal history of
    febrile seizures, SUDC with a family history of febrile seizure, and SUDC with no personal or
    family history of seizures. Pet. Ex. 18 at 11 tbl.2. Seven SUDC cases had a family history of
    febrile seizures. 
    Id.
     In this group, three children had hippocampal areas available for
    examination, and two of these three exhibited hippocampal abnormalities, specifically in the
    dentate gyrus. 
    Id. at 5
    , 11 tbl.2, 12 tbl.3. Additionally, four of the seven (57%) had fever and all
    seven (100%) were found in their sleep in the prone position. 
    Id.
     at 11 tbl.2.
    Based on this study, Kinney et al. stated “that a subset of SUDC cases is characterized by
    an individual and/or family history of febrile seizures and hippocampal maldevelopment.” Pet.
    Ex. 18 at 5. They hypothesized a new entity of SUDC cases “defined by unwitnessed sleep-
    related, sudden death and hippocampal/temporal lobe maldevelopment and characterized by an
    individual and/or family history of febrile seizures and prone sleep position, often face-down, at
    discovery.” 
    Id.
     They stressed the “defining feature[s]” of this entity are abnormalities in the
    hippocampus and temporal lobe and “individual and/or family histories of febrile seizures are
    important risk factors for sudden death in association with this [] pathology.” 
    Id. at 5-6
    .
    Kinney et al. further stated that the abnormalities seen in the temporal lobe, in
    conjunction with SUDEP cases, “suggests the possibility that affected toddlers experience an
    unwitnessed, sleep-related seizure that originates in the anomalous epileptogenetic focus in the
    27
    Jenna Harowitz et al., Seizure-Related Deaths in Children: The Expanding Spectrum, 62
    Epilepsia 570 (2021).
    16
    hippocampus, resulting in upper airway occlusion/cardia arrythmia/hypotension, and fetal
    cardiopulmonary arrest.” Pet. Ex. 18 at 6. They “speculate[d]” that in this entity of SUDC
    cases, “a terminal and fatal seizure leads to death . . . due to seizure-induced upper airway
    occlusion, augmented by airway compression in the prone (face-down) position.” 
    Id.
    Respiratory tract infections were noted as a “potential triggering factor.” 
    Id.
    In 2014, Kinney et al. examined 153 autopsies of infants with sudden and unexpected
    death and found hippocampal pathology—bilamination and granule cell dispersion—present in
    47 of 114 (41.2%) of the unexplained death group and 3 of the 39 (7.7%) of the explained death
    group. Pet. Ex. 26 at 2, 6. A 2016 article authored by Kinney et al. stated that hippocampal
    abnormalities in the dentate gyrus were associated with sudden death in children regardless of
    age. Pet. Ex. 29 at 3. Kinney et al. examined 32 cases with hippocampal abnormalities, 17 of
    which were over the age of one. 
    Id. at 4
    . Of those 17 cases, 16 were sleep-related deaths and 13
    were found in the prone position. 
    Id.
     at 4 tbl.1. Dentate bilamination was found in 31 of the 32
    cases, or 18 of the 19 children over one year of age. 
    Id. at 5
    . Additionally, nine cases had a
    family history of seizures and 22 had a family history of febrile seizures and/or epilepsy. 
    Id.
    Kinney et al. stated that “[t]he neuropathological findings . . . provide[d] a plausible mechanism
    for sudden and unexpected death via an epilepsy-like mechanism.” 
    Id. at 13
    . Specifically they
    stated seizures “may be generated in the abnormal [hippocampus]” and “triggered by stress (e.g.
    asphyxia or fever).” 
    Id.
     None of the Kinney et al. articles discussed vaccinations, or any
    potential role of vaccinations.
    Similar findings were reported by Hefti et al. 28 in 2016. Pet. Ex. 28. Hefti et al.
    examined 83 cases with at least one hippocampal section for microscopic review. 
    Id. at 5
    . They
    classified these 83 cases into subgroups, including a subgroup of SUDC without hippocampal
    pathology or febrile seizure phenotype (22/83) and a subgroup termed “hippocampal
    maldevelopment associated with sudden death,” or HMASD (40/83). 
    Id. at 2
    . For the HMASD
    cases, 95% died during sleep and 85% were discovered in the prone position. 
    Id. at 5
    . Twenty-
    five of the 40 (62.5%) had a personal and/or family history of febrile seizures, and 15 of the 40
    (37.5%) had only a family history of febrile seizures. 
    Id.
     Additionally, 20 had a fever within 48
    hours of death. 
    Id.
     at 6 tbl.2. For the 22 SUDC cases without hippocampal pathology or febrile
    seizure phenotype, 13 (59.1%) had a fever within 48 hours of death, 21 (95.5%) died during
    sleep, and 13 (61.9%) were found in the prone position. 
    Id.
    Hefti et al. hypothesized that the death in the HMASD cases “may be related to an
    unwitnessed seizure during sleep that originates in the malformed hippocampus,” which they
    noted “is supported by the reported association of hippocampal malformations in [SUDEP] [and]
    those in HMASD.” Pet. Ex. 28 at 9. They also hypothesized that “potential triggering events are
    sleep itself, fever, unwitnessed febrile seizure, and/or prone sleep.” 
    Id.
     Because none of the
    deaths in the HMSAD cases were witnessed, Hefti et al. concluded that “the direct relationship
    of febrile seizures (or hippocampal maldevelopment) to death is unknown.” 
    Id. at 11
    .
    28
    Dr. Kinney is also an author on this publication.
    17
    Kon et al. (2020) 29 reviewed cases of SIDS (358), SUDC (48), and SUDEP (18) to
    determine the prevalence of hippocampal abnormalities, history of seizures, and demographic
    features. Pet. Ex. 73 at 2. Their findings revealed hippocampal abnormalities 30 associated with
    temporal lobe epilepsy in 16 of 36 31 (44.4%) of SUDC cases. 
    Id. at 2
    , 5 tbl.2. Five of 11 SUDC
    cases with a history of afebrile seizures demonstrated hippocampal abnormalities, and none of
    the four SUDC cases with a history of febrile seizures displayed abnormalities in their
    hippocampus. 32 
    Id. at 2, 10
    . Most SUDC cases (27) were found in the prone position and half
    (24) experienced illness 33 within their last 72 hours. 
    Id.
     at 5 tbl.2.
    The authors noted that “[a]s hippocampal abnormalities are strongly associated with
    epilepsy, . . . researchers [have] hypothesize[d] that SUDC is ‘epilepsy in situ.’” Pet. Ex. 73 at
    10. Although none of their SUDC cases with a febrile seizure history had hippocampal
    abnormalities, the authors noted such link is well-documented and analogous to SUDEP, opining
    “[h]ippocampal abnormalities could predispose certain individuals to seizures in the event of a
    precipitating event such as infection.” 
    Id.
     Because hippocampal abnormalities were more likely
    to be seen in SUDC and SUDEP cases, the authors “suggest[ed] that the hippocampus likely
    plays a major role in SUDC and SUDEP.” 
    Id. at 11
    . Additionally, because an association
    between a history of seizures and prone sleeping position has been suggested, the authors noted a
    “possible explanation . . . is that these children may had experienced an unwitnessed seizure
    whilst in a prone position and being unable to free themselves from this position, asphyxiate,
    resulting in death.” 
    Id. at 10
    .
    Dr. Miller acknowledged that a more recent article from 2021, authored by Leitner et
    34
    al., reported “the lack of association of hippocampal findings in SUDC in controls as well as
    inconsistency of observations by multiple blinded reviewers indicates discrepancy with previous
    studies.” Tr. 53-54 (citing Resp. Ex. K at 2); see also Pet. Ex. 69 at 3. In Leitner et al.,
    hippocampal specimens from 19 SUDC and 26 sudden explained deaths in children (“SEDC”)
    control cases were reviewed by nine different reviewers from three types of pathologists
    (forensic pathologists, neuropathologists, and dual-certified neuropathologists/forensic
    pathologists). Resp. Ex. K at 1, 3. The reviewers reported a similar frequency of findings
    29
    Fu Chuen Kon et al., Hippocampal Abnormalities and Seizures: A 16-Year Single Center
    Review of Sudden Unexpected Death in Childhood, Sudden Unexpected Death in Epilepsy and
    SIDS, 16 Forensic Sci. Med. & Pathology 423 (2020).
    30
    For the specific hippocampal abnormalities seen, see Pet. Ex. 73 at 8 tbl.6.
    31
    Only 36 of the 48 SUDC cases had this information available. Pet. Ex. 73 at 5 tbl.2, 7.
    32
    Family history of seizures was not documented. See Pet. Ex. 73.
    33
    Fever was not included in this category. Pet. Ex. 73 at 4 tbl.1.
    34
    Dominique F. Leitner et al., Blinded Review of Hippocampal Neuropathology in Sudden
    Unexplained Death in Childhood Reveals Inconsistent Observations and Similarities to
    Explained Paediatric Deaths, 2021 Neuropathology & Applied Neurobiology 1.
    18
    relative to the hippocampal slides from the SUDC and control cases. 
    Id. at 9
    . Also, the
    reviewers were in agreement about hippocampal findings in SUDC cases with or without a
    history of febrile seizure. 
    Id.
     However, “half of the slides were reported as abnormal (SUDC
    52.5%, control 53.0%), indicating a potential range in as yet unidentified normal variation,
    undiagnosed pathology[,] or phenomena unrelated to SUDC or febrile seizures.” 
    Id.
     The
    authors concluded that the “discordance among reviewer groups indicates a discrepancy with
    previous studies and a need for larger consensus studies to standardise hippocampal findings to
    identify both the range of normal variation and pathology or phenomenon unrelated to SUDC or
    febrile seizures.” 
    Id. at 11
    .
    Dr. Miller argued the study “ha[d] multiple flaws,” including a lack of critical analysis as
    to whether the cause of death was correctly determined by the original pathology, which “could
    have [] tainted” the control group with cases that should have been classified as SUDC and were
    not. Pet. Ex. 69 at 3.
    Dr. Miller also discussed an unpublished study he worked on that found dentate gyrus
    dysplasia “is very common in the general autopsy population at all ages and with [various]
    causes of death.” Pet. Ex. 22 at 6; see also Pet. Ex. 69 at 3-4. The study was a retrospective
    review of autopsies with neuropathology examinations from 2008 through 2016. Tr. 41; Pet. Ex.
    69 at 3. In total, 962 autopsies were examined, including all age ranges. Tr. 41; Pet. Ex. 69 at 3.
    Dr. Miller explained that 201 of the 962 displayed “at least one dentate gyrus with dysplasia,
    whether granule cell dispersion with or without bilamination, duplications, or hyperconvolutions
    (or combinations thereof).” Pet. Ex. 69 at 3. He concluded that “in the general autopsy
    population, including cases of SIDS, SUDC, and SUDEP, there were dentate gyrus abnormalities
    in 20.8% of the cases.” 
    Id.
     The study population had 11 cases of SUDC, seven (63.6%) of
    which had definite dentate gyrus abnormalities. 
    Id. at 4
    . Given this data, Dr. Miller asserted
    “the incidence of dentate gyrus dysplasia in SUDC cases . . . is at least [three] times that in the
    general population (63% to 21%).” 
    Id.
     He acknowledged, however, that he did not have
    statistical testing completed on this data. 
    Id.
     As of July 2022, his study was not yet peer-
    reviewed or sent for publication. Tr. 40. Nor was the study filed in this case.
    Two case reports were filed by Petitioners. Dlouhy et al., 35 in 2017, described a child
    with a history of two witnessed complex febrile seizures who died suddenly and unexpectedly
    following a suspected unwitnessed seizure during sleep; the death was classified as a SUDEP.
    Pet. Ex. 70 at 2. The authors wrote, “[a]lthough some cases of [SUDC] have a history of febrile
    seizures, no documented case of febrile seizure-induced death has been reported.” 
    Id.
     They
    suggested that “febrile seizures can lead to sudden unexpected death in children through
    mechanisms similar to those involved in SUDEP.” 
    Id. at 4
    . However, Dlouhy et al.
    acknowledged that a seizure may not have occurred. 
    Id.
     The authors did not discuss vaccines.
    35
    Brian J. Dlouhy et al., Unexpected Death of a Child with Complex Febrile Seizures—
    Pathophysiology Similar to Sudden Unexpected Death in Epilepsy?, 8 Frontiers Neurology 1
    (2017).
    19
    Similarly, Myers et al. (2017) 36 reported the case of a 20-month-old girl with a complex
    chromosomal disorder and episode of febrile status epilepticus, 37 who died suddenly and
    unexpectedly during a video electroencephalogram (“EEG”). Pet. Ex. 71 at 2. The “sequence of
    physiologic changes leading up to death suggest[ed] a pathophysiology similar to [SUDEP].” 
    Id.
    The child did not meet the criteria for an epilepsy diagnosis, and thus the death was classified as
    a SUDC. 
    Id. at 4
    . However, the authors suggested that the mechanism of her death was
    “SUDEP-like” following febrile seizure. 
    Id. at 5
    . Vaccinations were not at issue.
    Dr. Miller acknowledged that epidemiological studies have conflicting findings regarding
    a connection with vaccination and sudden unexpected deaths. Pet. Ex. 22 at 9. He cited various
    studies that found no causal relationship between vaccinations 38 and sudden unexpected deaths.
    See, e.g., Pet. Ex. 40 at 2; 39 Pet. Ex. 41 at 3 (finding “no way to prove that the[ir] infant deaths
    [were] caused by vaccination”); 40 Pet. Ex. 44 at 18 (concluding “[t]he evidence does not indicate
    a causal relation between [diphtheria-pertussis-tetanus (“DPT”)] vaccine and SIDS”). 41 He also
    cited studies on SIDS. See, e.g., Pet. Ex. 45; 42 Pet. Ex. 46 at 2 (“There is no increased or
    reduced risk of sudden infant death during the period after the vaccination.”). 43 He argued that
    there are various flaws in these studies, and in his view, epidemiology “does not provide any
    answer to the question of a possible causal relationship between vaccinations and SIDS.” Pet.
    Ex. 22 at 9. However, Dr. Miller maintained “there is a scientifically and medically plausible
    means to connect these events.” 
    Id.
    36
    Kenneth A. Myers et al., Sudden Death After Febrile Seizure Case Report: Cerebral
    Suppression Precedes Severe Bradycardia, 140 Pediatrics 1 (2017).
    37
    Status epilepticus is “a prolonged series of seizures without return to full consciousness
    between them.” Status Epilepticus, Dorland’s Med. Dictionary Online,
    https://www.dorlandsonline.com/dorland/definition?id=108327 (last visited Nov. 13, 2023).
    38
    MMRV and MMR vaccinations were not included in these studies.
    39
    Rüdiger von Kries et al., Sudden and Unexpected Deaths After the Administration of
    Hexavalent Vaccines (Diphtheria, Tetanus, Pertussis, Poliomyelitis, Hepatitis B, Haemophilius
    Influenzae Type B): Is There a Signal?, 164 Eur. J. Pediatrics 61 (2005).
    40
    B. Zinka et al., Unexplained Cases of Sudden Infant Death Shortly After Hexavalent
    Vaccination, 24 Vaccine 5779 (2006).
    41
    Inst. of Med., Evidence Concerning Pertussis Vaccines and Deaths Classified as Sudden Infant
    Death Syndrome, in Adverse Effects of Pertussis and Rubella Vaccines 125 (Christopher P.
    Howson et al. eds., 1991).
    42
    M.M.T. Vennemann et al., Do Immunizations Reduce the Risk for SIDS? A Meta-Analysis, 25
    Vaccine 4875 (2007).
    43
    Ronny Kuhnert et al., Reanalyses of Case-Control Studies Examining the Temporal
    Association Between Sudden Infant Death Syndrome and Vaccination, 30 Vaccine 2349 (2012).
    20
    Dr. Miller concluded that his theory, or “chain of events[,] represents a highly plausible,
    scientifically valid, hypothesis.” Pet. Ex. 22 at 13. He acknowledged “[t]here are no
    experimental or clinical studies possible to fully prove [his] hypothesis” in this case. 
    Id.
    iii.   Althen Prongs Two and Three
    Dr. Miller opined the MMRV vaccination administered to N.A. on June 23, 2016 caused
    N.A. to develop a fever, and this vaccine-induced fever provoked a seizure on June 30 that
    resulted in N.A.’s death due to her unknown vulnerability. Tr. 21-22, 25, 34-35; Pet. Ex. 69 at 1-
    2.
    First, he noted there is evidence N.A. had a fever on the night of June 30, 2016, within
    the risk period following MMRV vaccines. Pet. Ex. 22 at 4, 12. He explained Petitioners
    reported on the morning of July 1, 2016 that N.A. “had been having episodic low grade fever, up
    to 100.5°F, since [June 13],” although “[t]his [was] not mentioned in the pediatrician’s records
    for the [June 23] visit.” Id.; see also Tr. 34.
    Dr. Miller opined that the fact that N.A. received Motrin around 7:00 p.m. on June 30
    does not suggest N.A. did not suffer a fever or febrile seizure. Tr. 234. He found this argument
    “speculative” and he argued that “Motrin is not 100[%] effective in reducing or preventing
    fever” and “Motrin won’t affect the development of fever.” Tr. 234-35. But see Pet. Ex. 21 at 7
    (“If MMRV continues to be offered for first-dose administration, it might be advisable to counsel
    parents regarding antipyretic use if children experience a fever within the peak risk period.”). 44
    Dr. Miller next opined N.A. suffered a seizure during the night of June 30, 2016 and cited
    four reasons for support: (1) N.A.’s family history of seizures; (2) N.A. received an MMRV
    vaccination within the appropriate time period; (3) N.A. was found dead in the prone position;
    and (4) N.A.’s autopsy abnormalities. Tr. 25-26.
    First, he noted N.A. had a positive family history of seizures (her brother), which he
    opined was evidence in favor of a finding that N.A. suffered a seizure on the night of June 30,
    2016. Tr. 25-26. Dr. Miller noted N.A.’s brother’s 3q29 microdeletion syndrome is separate
    from his history of febrile seizures because seizures have not been found to be related to a 3q29
    microdeletion syndrome. Tr. 231-32, 248; see also Pet. Ex. 79 at 8 (finding “seizures are not a
    significant part of the 3q29 deletion phenotype,” and thus, “the neurodevelopmental pathway
    affected by 3q29 deletion is . . . not [relevant to] epilepsy or seizure”). 45
    44
    Dr. Miller agreed this happened here. Tr. 248-49. An antipyretic is “an agent that relieves
    fever.” Antipyretic, Dorland’s Med. Dictionary Online, https://www.dorlandsonline.com/
    dorland/definition?id=3479 (last visited Nov. 13, 2023).
    45
    Megan R. Glassford et al., Novel Features of 3q29 Deletion Syndrome: Results from the 3q29
    Registry, 170 Am. J. Med. Genetics 999 (2016).
    21
    Second, he noted N.A. received an MMRV vaccination seven to 10 days prior to her
    development of a fever and her death, which is within the risk period for seizures post-MMRV
    vaccination. Tr. 25, 34. Third, N.A. was found dead in a prone position, which he explained “is
    a common position for those with SUDEP, . . . [SUDC], and [] in SIDS.” Tr. 25.
    And fourth, he opined N.A.’s autopsy supports a finding that N.A. suffered a seizure the
    night of June 30 because (1) no definite cause of death was found on autopsy and (2) N.A.’s
    brain slides showed abnormalities consistent with SUDC. Tr. 25-26. Specifically, the autopsy
    and police investigation showed no evidence of trauma, no toxins, no anatomical cause of death
    (no infectious process), no developmental abnormality, and “no specific finding” as to what
    caused N.A.’s death. Tr. 22, 25-26; Pet. Ex. 22 at 4. Additionally, Dr. Miller examined the
    autopsy slides and found most showed “no significant abnormality of any kind, no infectious
    process, no developmental abnormality, [and] no signs of trauma.” Tr. 22. However, he
    observed two significant abnormalities on the brain slides that he explained were commonly seen
    in SUDC cases in association with febrile seizures. Tr. 25-26, 35; Pet. Ex. 22 at 12.
    According to Dr. Miller, the first abnormality was in N.A.’s hippocampus, which he
    explained exhibited a dysplastic, or abnormally formed, dentate gyrus. Tr. 23, 28-29 (citing Pet.
    Ex. 66 at 3); see also Pet. Ex. 22 at 4-6. Specifically, he found granule cell dispersion including
    bilamination. 46 Tr. 23, 28-29 (citing Pet. Ex. 66 at 3, 7); see also Pet. Ex. 22 at 4-6.
    The second brain abnormality Dr. Miller found on the autopsy slides dealt with the
    medulla. Tr. 23. He opined “the slide of the medulla showed some patches in the medulla which
    were lacking neurons[] [and] lacking nerve cells, suggestive of a developmental abnormality or
    perhaps other unappreciated episodes of anoxia in the medulla, although there were no other
    signs of anoxia anywhere else in the brain.” 
    Id.
     Specifically, he found a “subtle depletion of
    large neurons from each inferior olivary nucleus along with a mild gliosis” and he opined this
    finding has been reported in autopsies of SIDS cases. Pet. Ex. 22 at 5, 8; see also Tr. 46-49; Pet.
    Ex. 65 at 2-3; Pet. Ex. 66 at 9. This abnormality is “thought to indicate either a developmental
    abnormality in medullary structures derived from the embryonic rhombic lip, or prior
    unrecognized episodes [] from which there had been spontaneous recovery.” Pet. Ex. 22 at 5, 8;
    see also Pet. Ex. 65 at 3. Dr. Miller opined that if N.A.’s case was viewed as a SIDS case,
    instead of SUDC, “the olivary abnormalities” would be “evidence of a rhombic lip problem that
    likely also affected some parts of the medullary 5HT system and predisposed [N.A.] to sudden
    death with exposure to additional risk factors,” or fever. Pet. Ex. 65 at 3.
    Because of the abnormalities identified by Dr. Miller in the brain autopsy slides, he
    opined N.A.’s MMRV vaccine put her at “greater risk.” Tr. 25. He opined that “more likely
    than not[,] these abnormalities represent the underlying vulnerability that made [N.A.’s] death
    possible.” Pet. Ex. 22 at 7. He found it “likely that both abnormalities played a role in [N.A.’s]
    death” because there are “connections between the medullary systems governing respiration and
    the cerebral hemispheric limbic system, notably the hippocampi.” 
    Id.
     During the hearing, Dr.
    Miller testified that the abnormality in N.A.’s hippocampus would be sufficient to have caused
    46
    For a further discussion of Dr. Miller’s opinions on bilamination, in general and in N.A.’s
    case, see Tr. 226-31, 235-37; Pet. Ex. 65 at 1-2; Pet. Ex. 26 at 8; Pet. Ex. 28 at 4.
    22
    her death. Tr. 50. He explained that “for those cases where there’s been an autopsy with a
    neuropathology examination, there’s a very strong indication that the hippocampal abnormalities
    are associated with a vastly increased risk, more than three times [the] risk, over the general
    population.” Tr. 51-52; see also Pet. Ex. 69 at 4.
    If, however, there were no abnormalities in the brain at autopsy, Dr. Miller concluded it
    would be “unknown” as to whether the vaccine was involved in N.A.’s death. Tr. 51 (stating
    “presumably” febrile seizures can be fatal in the absence of hippocampal abnormalities).
    During the hearing, Dr. Miller was questioned about the report from SUDCRRC,
    specifically the fact that the neuropathologist and forensic pathologist who reviewed the brain
    slides did not report any abnormalities, which he did not review prior to or during the hearing.
    Tr. 237-38. He could not account for why he found abnormalities in the hippocampus when the
    SUDCRRC noted no abnormalities. Tr. 238-41. Dr. Miller testified that he was unable to
    comment without knowing the neuropathologist that examined the hippocampus or what slides
    of the hippocampus were examined. 
    Id.
    Next, Dr. Miller compared the facts in N.A.’s case to those deaths that occur in those
    with epilepsy. Tr. 35-36. He explained “[it is] very well documented that patients who have a
    known history of epilepsy have an increased risk for sudden unexpected death, those deaths
    almost always [] com[e] out of sleep or during sleep, [and they are] almost always found in bed
    face down.” Tr. 36. Such cases are referred to as SUDEP, although he agreed that N.A.’s case
    was not SUDEP. Tr. 36, 42, 45.
    On cross-examination, Dr. Miller maintained that the “terminal event” in N.A.’s case was
    a febrile seizure that led to apnea or cardiac arrhythmia and cardiac arrest. Tr. 62. He
    acknowledged that his theory is “not very well understood because it’s such a rare event and
    [there have] been no animal model or human studies which have fully documented in a large
    enough number of cases to have some certainty about the actual mechanism.” 
    Id.
     He opined
    there was a “very small” likelihood that N.A. could suffer from apnea or cardia arrhythmia and
    cardiac arrest without the MMRV vaccination. 
    Id.
     But he emphasized that “SUDC is a very rare
    event[,] . . . far less common than SIDS.” 
    Id.
    Dr. Miller had no opinion on how long N.A.’s seizure lasted. Tr. 44-45. Given his
    experience in forensic pathology and as a medical examiner, he opined that the time of death is
    “highly subjective” and “subject to many variables.” Tr. 246. Time of death is “an
    approximation” that “could be off by several hours in either direction.” 
    Id.
    Regarding Dr. Vargas’ opinion that N.A. had a viral infection at the time of death, Dr.
    Miller responded by opining that it was “implausible” without better evidence. Tr. 58-59. But
    see Pet. Ex. 22 at 8 (noting N.A. “did not clearly have an upper respiratory infection prior to her
    death, although the intermittent low grade fever . . . might represent such condition”). Dr. Miller
    was also not persuaded by Dr. Vargas’ opinion that N.A. had a chronic respiratory viral
    infection. Pet. Ex. 65 at 3-4.
    23
    On July 1, 2016, N.A.’s sister, L.A., had “yellow nasal crusting.” Tr. 59. Dr. Miller
    agreed this would indicate an infection, which he called a “common cold.” 
    Id.
     He opined that a
    cold is not usually associated with a fever. Tr. 59-60. Even if N.A.’s twin sister L.A. had a viral
    infection on July 1, Dr. Miller maintained that N.A.’s fever would still be caused by her MMRV
    based on “statistics.” Tr. 60. His reliance on statistics is that “children get colds, and they don’t
    generally die of them. . . . There is a described increased risk for both fever and febrile seizures
    in children who got the MMRV vaccine . . . . It’s still a very rare event, but it’s a definite
    increased incidence.” 
    Id.
    Further, Dr. Miller was not persuaded by Dr. McCusker’s arguments that N.A.’s mucus
    in her airways led to her death. Pet. Ex. 65 at 3. Dr. Miller argued Dr. McCusker misstated the
    autopsy findings because only a “[s]mall amount of mucus” was present. 
    Id.
     (quoting Pet. Ex. 6
    at 2). He asserted that Dr. McCusker’s theory, which is based on the belief that infants only
    breathe out of their nose and cannot switch to breathing out of their mouth, is without
    foundation. 
    Id.
    He concluded that the combination of factors here, including N.A.’s fever on the night of
    June 30, 2016, N.A.’s receipt of MMRV vaccination seven days prior, N.A.’s family history of
    seizures, N.A.’s prone position on death, and N.A.’s autopsy findings, constitutes compelling
    evidence that N.A.’s MMRV vaccination triggered a fever that led to a seizure that subsequently
    caused her death. Tr. 34-36, 69; Pet. Ex. 69 at 2.
    2.      Petitioners’ Expert, Marcel Kinsbourne, M.D. 47
    a.      Background and Qualifications
    Dr. Kinsbourne is a neurologist and pediatric neurologist. Tr. 88-89. In 1955, he
    obtained his B.M., B.Ch. from Oxford University Medical School, and he completed
    postdoctoral training through 1964 in the United Kingdom. Pet. Ex. 14 at 1. Thereafter, he
    obtained board certification and licensing in the United States and Canada and worked as a
    professor at various teaching institutions. 
    Id. at 1-2
    . Dr. Kinsbourne has served and is currently
    serving on a number of editorial boards. 
    Id. at 3-4
    . He has authored or co-authored more than
    400 publications. 
    Id. at 5-39
    . Dr. Kinsbourne is no longer a practicing physician and no longer
    works as a professor at the New School University in New York. Tr. 90. He has not practiced
    clinical medicine or worked in a hospital since 1981. 
    Id.
    b.      Opinion
    Dr. Kinsbourne opined that “more likely than not[,] [] the fever and seizure generated by
    the MMRV [vaccination] was . . . the cause of [N.A.’s] death.” Tr. 78; see also Pet. Ex. 13 at 4;
    Pet. Ex. 61 at 3.
    47
    Dr. Kinsbourne provided two expert reports and testified at the hearing. Pet. Exs. 13, 61; Tr.
    3. Dr. Kinsbourne cited and discussed some of the same literature as Dr. Miller. For sake of
    brevity, the undersigned will not repeat those studies.
    24
    i.     Althen Prong One
    Dr. Kinsbourne opined that the MMRV vaccine can trigger an unwitnessed seizure that
    can cause death. Pet. Ex. 13 at 3-4; Pet. Ex. 61 at 2-3.
    Dr. Kinsbourne began by explaining that is it well-known that the MMRV vaccine can
    cause fevers and febrile seizures between seven to 10 days post vaccination. Tr. 76; see also Pet.
    Ex. 19 at 2; Pet. Ex. 21 at 2; Pet. Ex. 61 at 1. He testified that “the MMRV vaccination is . . . the
    most prone to cause the adverse effects of fever and seizure, in other words, febrile seizure,
    within an appropriate time frame.” Tr. 78-79. According to Dr. Kinsbourne, a child who
    receives an MMRV vaccination is seven times more likely to have a seizure seven to 10 days
    following administration. Tr. 79, 105. He also opined that a fever increases the risk of a seizure,
    especially in children between the ages of six months and six years, with a peak at year two. Tr.
    80. At the hearing, Dr. Kinsbourne did not indicate which studies support these statistics. In his
    expert reports, he cited studies that compared the risk of seizures between the MMRV vaccine
    and the MMR and separate varicella (“MMR+V”) vaccines. See Pet. Exs. 19, 21. MacDonald et
    al. showed that the risk of seizures was higher after MMRV as compared to MMR+V; however
    Klein et al. did not find a significantly increased risk with the MMRV vaccine. Pet. Ex. 19 at 2,
    8; Pet. Ex. 21 at 2. Both studies showed that both MMRV and MMR+V “are associated with
    fever and seizure [seven] to 10 days after vaccination,” but neither reported increase of seven
    fold, as testified to by Dr. Kinsbourne. Pet. Ex. 19 at 8; see also Pet. Ex. 21 at 2. When asked to
    identify the study that reported a seven-fold increase in seizures following the MMRV
    vaccination, Dr. Kinsbourne was unable to remember the name of the article. Tr. 105-07.
    Next, Dr. Kinsbourne opined febrile seizures can lead to death in certain circumstances
    depending on the seizure threshold of the individual and risk factors. Tr. 84, 251; Pet. Ex. 13 at
    3; Pet. Ex. 61 at 2-3. He explained that febrile seizures are “really common” and occur in two to
    five percent “of all children.” Tr. 85. He testified that most are short and benign, but some
    (30%) may be prolonged, and thus, dangerous. 
    Id.
     “In a healthy child and an uncomplicated
    setting[,] a simple febrile seizure would indeed not be considered potentially fatal.” Pet. Ex. 61
    at 3.
    He testified that unobserved seizures “undoubtedly” occur and can cause death. Tr. 84-
    85; see, e.g., Pet. Ex. 18. He added that the risk of impaired respiration is less likely in a
    witnessed febrile seizure than in an unwitnessed seizure because interventions can occur when a
    seizure is witnessed. Pet. Ex. 61 at 3. Such lack of intervention “is especially true of
    unwitnessed seizures that occur during sleep.” Id.; see also Tr. 80-81 (opining sleep increases
    the risk of seizures); Pet. Ex. 18 at 6. Dr. Kinsbourne maintained that “[t]he rarity of death due
    to a witnessed febrile seizure does not suggest that unwitnessed febrile seizures don’t cause
    death.” Pet. Ex. 61 at 3.
    Dr. Kinsbourne explained that a family history of febrile seizures is “a risk factor for
    febrile seizures in a member of that family.” Tr. 78. He added that “[a] family history makes it
    more likely that the seizure occurs in a given child.” Tr. 103. Additionally, “[a] family history
    of febrile seizures is found in a disproportionate percentage of infants who die in a sudden
    unexpected death.” Pet. Ex. 13 at 3.
    25
    For support, he cited Hesdorffer et al. 48 and argued they “proposed that children with
    [SUDC] who had a family history of febrile seizures had an increased risk of dying in a terminal
    seizure.” Pet. Ex. 13 at 2 (citing Pet. Ex. 16 at 2). They examined 123 SUDC cases and found
    31.7% had a personal history of febrile seizures, 18.7% had a first-degree family history of
    febrile seizures, 96.8% died during sleep and the death was unwitnessed, 73.9% were found in
    the prone position at death, and 75.6% had a terminal fever or illness symptoms within 48 hours
    before death. Pet. Ex. 16 at 5, 4-5 tbl.1. Of the 84 SUDC cases without a personal history of
    febrile seizure, 75.9% had a terminal fever or illness symptoms within 48 hours of death, 70.1%
    were found in the prone position at death, and 14.3% had a first-degree family history of febrile
    seizures. 
    Id. at 6
    , 4-5 tbl.1. Hesdorffer et al. found that “[i]n children with SUDC and a history
    of [febrile seizure], terminal fever may increase the risk for an unwitnessed terminal seizure.”
    
    Id. at 2
    . Dr. Kinsbourne acknowledged that this finding relates to a personal history of febrile
    seizures, and not a family history of febrile seizures. Tr. 103. Hesdorffer et al. could not
    “exclude the possibility in these unwitnessed deaths that among the 75.9% of children with
    terminal fever or illness symptoms but without a prior [febrile seizure], their first [febrile
    seizure] might have been a terminal event.” Pet. Ex. 16 at 7.
    Another article cited by Dr. Kinsbourne reported a similar conclusion related to children
    who had a history of febrile seizures. Crandall et al. 49 determined “[p]atients with febrile
    seizures are at [an] increased risk for sudden death.” Pet. Ex. 72 at 2. The authors examined and
    interviewed 391 families where a child aged one to six died, and 264 were classified as SUDC.
    
    Id. at 4
    . Of these 264 cases, 181 did not have any seizure history, 76 had a febrile seizure
    history, and seven had an afebrile seizure history. 
    Id.
     First- and second-degree family history of
    febrile seizures was found in 45 of 160 cases of SUDC without a personal seizure history. 
    Id.
     at
    5 tbl.1. Crandall et al. found SUDC cases with a personal history of febrile seizures were more
    likely to have a family history of seizures, both febrile and afebrile. 
    Id. at 6
    . Additionally, 253
    of 264 (95.8%) SUDC cases were found unresponsive during a sleep period and 173 of 211
    (82%) were discovered in the prone position. 
    Id. at 5
    . In 112 of 245 SUDC cases (45.7%), a
    terminal fever was reported. 
    Id.
     Crandall et al. concluded their “findings implicate [febrile
    seizure] as a contributing factor or cause of death via a SUDEP-like process in some SUDC
    cases.” 
    Id. at 6
    . The authors, however, “speculate[d] that [febrile seizures] occur in some
    children without a known [febrile seizure] history.” 
    Id. at 7
    . They added, “[p]ostmortem
    evidence of terminal seizures is often absent or nonspecific . . . . Explained deaths attributed to
    asphyxia could include [febrile seizure] cases where the child remained prone . . . .” 
    Id.
    Dr. Kinsbourne also cited medical literature relating to SUDEP and found this literature
    can relate to SUDC, explaining “[SUDEP] literature suggests indirectly, not with certainty, that
    in SUDC, there is, indeed, a tendency for the child to have had a history of febrile seizures, . . .
    48
    Dale C. Hesdorffer et al., Sudden Unexplained Death in Childhood: A Comparison of Cases
    with and Without a Febrile Seizure History, 56 Epilepsia 1294 (2015).
    49
    Laura Gould Crandall et al., Potential Role of Febrile Seizures and Other Risk Factors
    Associated with Sudden Deaths in Children, 2 JAMA e192739 (2019).
    26
    either a personal history or family history of febrile seizures.” Tr. 82-83, 256. Dr. Kinsbourne
    cited Devinsky, 50 who suggested that cases of SUDEP may occur after a seizure, usually a tonic-
    clonic seizure. Pet. Ex. 15 at 3. Findings that may be seen include bitten tongue or cheek and
    pulmonary edema. 
    Id. at 2
    , 9 tbl.3. The finding of pulmonary edema was not explained.
    Devinsky also suggested that there may be impaired respiration following a seizure, which may
    be lethal and involve pulmonary dysfunction. 
    Id. at 5
    , 6 tbl.2.
    Kloster and Engelskjøn 51 examined risk factors and their role in SUDEP. Pet. Ex. 20 at
    2. Of the 42 cases classified as SUDEP with no verified cause of death, 62% had pulmonary
    edema, 67% showed signs of a preceding seizure, 71% were found in the prone position at death,
    and 60% were found in bed “presumably dying before, during, or after sleep.” 
    Id. at 2, 4-5
    . The
    authors noted signs of seizures immediately before death included fresh bites, blood on the
    pillow, cyanosis, 52 and sounds associated with ongoing seizures. 
    Id. at 3
    . “The prone position
    may cause obstruction of the nose and mouth due to pressure against the bed clothing.” 
    Id. at 5
    .
    The authors hypothesized that those who were found dead in bed may have died due to their
    positioning or due to sleep itself, which would implicated the respiration. 53 
    Id. at 6
    . Kloster and
    Engelskjøn noted, “[c]learly[] seizures play an important part in SUDEP, but some patients die
    without visible seizures,” and thus, there is a “possibility that some of these deaths are unrelated
    or only indirectly related to epilepsy.” 
    Id. at 5
    .
    Dr. Kinsbourne also cited Kinney et al. (2009) and Hefti et al., discussed in more detail
    above, which reported an association of sudden death, febrile seizures, hippocampal
    abnormalities, and sleep. Pet. Ex. 13 at 2 (citing Pet. Ex. 18); Pet. Ex. 61 at 3 (citing Pet. Exs.
    27-28). Kinney et al. “suggest[ed] that simple febrile seizures may not be totally benign,” and
    found a group of deaths characterized by sleep-related unwitnessed sudden death in the toddler in
    the prone position, individual/family history of febrile seizures, and hippocampal anomalies.”
    Pet. Ex. 18 at 7. Based on the medical literature, Dr. Kinsbourne opined febrile seizures can be
    lethal in certain circumstances. Pet. Ex. 61 at 3.
    50
    Orrin Devinsky, Sudden, Unexpected Death in Epilepsy, 
    365 New Eng. J. Med. 1801
     (2011).
    51
    Robert Kloster & Torstein Engelskjøn, Sudden Unexpected Death in Epilepsy (SUDEP): A
    Clinical Perspective and a Search for Risk Factors, 67 J. Neurology Neurosurgery & Psychiatry
    439 (1999).
    52
    Cyanosis is “a bluish discoloration, especially of the skin and mucous membranes due to
    excessive concentration of deoxyhemoglobin in the blood.” Cyanosis, Dorland’s Med.
    Dictionary Online, https://www.dorlandsonline.com/dorland/definition?id=12098 (last visited
    Nov. 13, 2023).
    53
    See also Pet. Ex. 17 (John Hewertson et al., Epileptic Seizure-Induced Hypoxia in Infants with
    Apparent Life-Threatening Events, 94 Pediatrics 148 (1994)) (explaining how epileptic seizures
    can be accompanied by episodes of hypoxia and apnea).
    27
    ii.    Althen Prongs Two and Three
    Dr. Kinsbourne opined the MMRV vaccine N.A. received on June 23, 2016 triggered a
    fever and an unobserved seizure that caused her death on June 30, 2016. Tr. 76-78; Pet. Ex. 13
    at 3-4; Pet. Ex. 61 at 2-3. He summarized that N.A. was at an increased risk for sudden
    unexplained death because her family history of febrile seizures put her at risk for a febrile
    seizure, her hippocampal abnormalities made her more susceptible to seizure generation, and
    sleep lowered her seizure threshold. Pet. Ex. 61 at 2. Because of this triad of risk factors, she
    was “vulnerable to the febrile seizure risk inherent in MMRV, to which she succumbed.” 
    Id.
    He explained N.A. received her MMRV vaccine on June 23, and seven days later, on
    June 30, she developed a fever. Tr. 79-80; Pet. Ex. 13 at 1-3. Because N.A.’s fever was within
    the risk interval following an MMRV vaccination, he opined “the presumption is that [the fever]
    was an MMRV fever.” Tr. 77; see also Pet. Ex. 61 at 3. Dr. Kinsbourne acknowledged that
    N.A.’s fever was a low-grade fever, and that Mrs. Anklam did not take N.A.’s temperature. Tr.
    92-93. He agreed that that literature associates febrile seizures with a certain threshold of
    temperature (about 102°F), but he opined that a temperature under 100°F can trigger a seizure
    depending on the individual’s seizure threshold. Tr. 107-08. However, he agreed that a
    temperature of less than a 100°F “would not be sufficient” to cause a seizure in most people. Tr.
    107. There would have to be “some genetic trait” to cause “relatively low seizure threshold.” 
    Id.
    He also agreed that N.A.’s seizure threshold was unknown. Tr. 108.
    He “assume[ed] that when [N.A.] had the seizure . . . , her temperature had gone
    considerably higher.” Tr. 94. “In other words, it was the beginning of a fever engendered by the
    vaccination.” 
    Id.
    Dr. Kinsbourne next opined that this fever caused by her MMRV vaccination led to an
    unobserved seizure that caused N.A.’s death due to her family history of seizures, prone position
    on death, and evidence of pulmonary edema and hippocampal abnormality on autopsy. Tr. 76-
    78; Pet. Ex. 13 at 3-4.
    As noted above, one of N.A.’s brother has a history of febrile seizures. Tr. 78, 98; Pet.
    Ex. 13 at 1-3. Dr. Kinsbourne opined “[a] family history of febrile seizure is found in a
    disproportionate percentage of infants who die a sudden unexpected death.” Pet. Ex. 13 at 3.
    Second, N.A. was found in the prone position on death, and Dr. Kinsbourne believed she
    was likely already unconscious when she got into this position. Tr. 86; Pet. Ex. 61 at 2. He
    added that this position would make it hard for her to breathe. Tr. 85-86. The medical examiner
    “could not explain why [N.A.] remained face down” and “cautioned that a one-year-old who is
    lying face down is capable of turning to the side if she becomes short of breath.” Pet. Ex. 13 at 2
    (citing Pet. Ex. 6 at 1); see also Pet. Ex. 61 at 2; Tr. 96. Dr. Kinsbourne agreed that children at
    one year of age “are well able to move their head sideways if the circumstances require it, which
    she clearly didn’t have that ability.” Tr. 86.
    Additionally, Dr. Kinsbourne opined this position at death was “suggestive of terminal
    seizure activity;” “the configuration of the body in rigor mortis was unusual, less like an infant
    28
    death by asphyxia than death during a seizure.” Pet. Ex. 13 at 2-3. He noted that although the
    medical examiner diagnosed death by asphyxia, the manner of death was undeterminable. 
    Id. at 2
    ; see Pet. Ex. 6 at 1 (“[N.A.] died of asphyxia. . . . The manner of death is undeterminable.”).
    And third, because pulmonary edema was found on autopsy, Dr. Kinsbourne opined that
    N.A.’s respiratory system likely was unable to maintain normal functioning for long enough for
    N.A. to survive, and lying on her face would have made it difficult to breathe. Tr. 85-86; Pet.
    Ex. 13 at 2. However, medical literature referenced by Dr. Kinsbourne does not show that the
    finding of pulmonary edema is specific to a seizure or evidence of a seizure. Although Devinsky
    noted “[s]eizure can cause pulmonary edema” and that “[p]ulmonary edema is the most common
    autopsy finding,” Devinsky failed to explain how a finding of pulmonary edema is specific to a
    seizure. Pet. Ex. 15 at 5, 6 tbl.2. Kloster and Engelskjøn observed the incidence of pulmonary
    edema in SUDEP cases, but they did not state that it was a sign of seizure. Pet. Ex. 20 at 3. And
    they did not attribute pulmonary edema specifically to seizures. 
    Id.
     Harowitz et al. described
    pulmonary edema as a non-specific finding. Pet. Ex. 74 at 5.
    At the hearing, Dr. Kinsbourne testified that his findings regarding N.A.’s hippocampal
    abnormalities are based on Dr. Miller’s opinions, and he acknowledged the medical examiner
    who conducted the autopsy found no abnormalities. Tr. 91-92; see also Pet. Ex. 13 at 2. Dr.
    Kinsbourne opined the hippocampal abnormality Dr. Miller described would double N.A.’s risk
    of seizure. Tr. 83. If N.A. did not have the hippocampal abnormality, Dr. Kinsbourne “would
    regard the evidence [in favor of a seizure the night of June 30, 2016] as less strong, but still
    easily strong enough.” 
    Id.
     He maintained “that more likely than not, N.A. did die because of the
    MMRV [vaccine] causing a febrile seizure which then precipitated her death as described” even
    without a hippocampal abnormality. Tr. 83, 102.
    Overall, Dr. Kinsbourne found “the presumption that there was a seizure [was] strong.”
    Tr. 84. “[A]nd if she had a seizure the possibility or the probability that it cause[d] her death
    [was] also strong, considering [] that there [were] no other factors in evidence that could have
    caused her death.” 
    Id.
     He opined it was “impossible” to know how long N.A.’s inferred seizure
    lasted. Tr. 85. He also acknowledged that N.A. had no history of seizure but hypothesized that
    “if N.A. had survived, she might have had the seizures subsequently or not.” Tr. 103.
    In response to Dr. Lidov’s arguments that N.A.’s absence of tongue biting was evidence
    against the existence of an unwitnessed seizure, Dr. Kinsbourne explained “[t]he absence of a
    lacerated tongue at [N.A.’s] autopsy is not useful criterion of whether a seizure occurred.” Pet.
    Ex. 61 at 2 (citing Pet. Ex. 28 at 6 tbl.2). Compare Pet. Ex. 20 at 3 (noting “fresh bites” to be a
    sign of a seizure), and Pet. Ex. 15 at 2, 9 tbl.3 (finding evidence of a seizure to include bitten
    tongue or cheek), with Pet. Ex. 72 at 7 (indicating tongue biting is an “infrequent” finding), and
    Pet. Ex. 74 at 5 (“In young children, seizures may lack classic signs (e.g., . . . tongue-biting),
    making diagnosis more difficult.”). He agreed with Dr. Lidov that “there is no direct scientific
    proof” a seizure occurred; however, he stressed that “there is ample circumstantial evidence
    [N.A.] died in a seizure.” Pet. Ex. 61 at 2.
    Regarding the length of N.A.’s seizure, Dr. Kinsbourne agreed that most febrile seizures
    are short and benign, but he explained if they are prolonged, they are more dangerous. Tr. 85.
    29
    Dr. Kinsbourne testified that it is “impossible to say how long N.A.’s inferred seizure was, but
    unfortunately, she died, and there was no other imaginable reason why she might have died.” 
    Id.
    Dr. Kinsbourne maintained there was no evidence of alternative causation. Pet. Ex. 13 at
    3; Pet. Ex. 61 at 3. In response to Dr. McCusker’s argument that N.A. had a viral respiratory
    infection that would have explained N.A.’s fever and blocked N.A.’s airway, Dr. Kinsbourne
    opined that no infection was diagnosed and the autopsy did not reveal an obstructed airway. Pet.
    Ex. 61 at 3. He added that any fever N.A. may have had in the week leading up to her MMRV
    vaccination “was evidently insufficient to provoke a seizure[] because it did not in fact do so.”
    
    Id.
     Lastly, he opined “[t]he fever at the time of [N.A.’s] death can more directly be attributed to
    the MMRV vaccination.” 
    Id.
    As for the temporal association between vaccination and seizure, Dr. Kinsbourne
    emphasized that N.A. had an elevated risk of seizure because she received her MMRV
    vaccination seven days prior to her death. Pet. Ex. 61 at 1-2.
    3.     Respondent’s Expert, Dr. Hart G.W. Lidov, M.D., Ph.D. 54
    a.      Background and Qualifications
    Dr. Lidov is a board-certified neuropathologist and pediatric neurologist, licensed in
    Massachusetts. Resp. Ex. E at 1-2; Resp. Ex. P at 6. He obtained his B.A. in Biophysics, Ph.D.
    in Anatomy, and M.D. from Johns Hopkins before completing a pediatric internship at
    Massachusetts General Hospital and residencies in pediatrics, neurology, neuropathology, and
    anatomic pathology at Massachusetts General Hospital, National Hospital Queens Square in
    London, UK, and Brigham and Women’s Hospital. Resp. Ex. P at 1. He held clinical
    fellowships in pediatrics, neurology, and pathology and neurology at Harvard Medical School
    and has been a Professor in pathology and neurology at Harvard Medical School for almost 20
    years. 
    Id. at 1-2
    . Since 1991, he has been a staff Neuropathologist at Boston Children’s Hospital
    and Brigham and Women’s Hospital. 
    Id. at 2
    . He “routinely see[s] surgical neuropathology
    cases from these hospitals, and autopsy examinations of the [central nervous system], as well as
    consultations.” Resp. Ex. E at 2. Dr. Lidov has authored or co-authored over 100 publications.
    Resp. Ex. P at 8-16.
    b.      Opinion
    i.      Althen Prong One
    Dr. Lidov opined that Petitioners’ theory that N.A.’s MMRV vaccination caused a fatal
    unwitnessed seizure was unlikely. Tr. 141-43. He explained that febrile seizures are uncommon
    and rare, and “a febrile seizure following a vaccination by itself is an extremely unlikely event.”
    Tr. 116-17 (citing Pet. Ex. 19). He did agree that the MMRV vaccine increases the risk of fevers
    and seizures in the period of seven to 10 days post-vaccination. Tr. 148. However, based on his
    personal experience and review the literature, Dr. Lidov opined that a first febrile seizure is not
    54
    Dr. Lidov submitted three expert reports and testified at the hearing. Resp. Exs. E, I, M; Tr. 3.
    30
    known to be fatal. Tr. 118-23; Resp. Ex. E at 4-5; Resp. Ex. M at 1. Further, since febrile
    seizures are the most common form of seizures in children, he expected that if there was an
    increase in mortality associated with an initial febrile seizure, it would probably be reported in
    the literature. Resp. Ex. E at 5; see also Resp. Ex. I at 13 (“If simple febrile seizures had the
    potential to be fatal, there should be reports, likely many reports . . . .”).
    For support, he cited Byard, 55 who stated that death during febrile seizures was rare.
    Resp. Ex. E at 5 (citing Resp. Ex. E, Tab 1 at 2). Shinnar and O’Dell 56 stated “[t]he morbidity
    and mortality associated with febrile seizures is extremely low,” and “[e]ven cases of febrile
    status epilepticus have shown almost zero mortality.” 
    Id.
     (quoting Resp. Ex. E, Tab 3 at 5); see
    also Resp. Ex. E, Tab 7 at 3 (“The mortality of febrile status epilepticus in recent series is
    extremely low.”); 57 Resp. Ex. U at 3 (“The mortality associated with febrile seizures is extremely
    low.”); 58 Resp. Ex. L at 2 (noting “the absolute risk of death [from febrile seizure] [is] [] very
    low”). 59 Dr. Lidov also cited Leung and Robson, 60 who similarly reported “[c]hildren with
    febrile seizures have no increased risk of mortality.” Resp. Ex. E at 5 (quoting Resp. Ex. E, Tab
    4 at 4 (internal citations omitted)).
    Dr. Lidov was not persuaded by Petitioners’ literature. Tr. 119-20 (citing Pet. Exs. 70-
    71); see also Resp. Ex. E at 5 (citing Pet. Ex. 70). Dlouhy et al., for example, noted “no
    documented case of febrile seizure-induced death has been reported” in SUDC, “[a]lthough some
    cases of [SUDC] cases have a history of febrile seizures.” Pet. Ex. 70 at 2. Dr. Lidov also
    explained that the Dlouhy et al. case report involved a child with a prior history of multiple
    complex seizures prior to the terminal event. Tr. 119 (citing Pet. Ex. 70 at 2). Based on this
    history, she would not be classified as SUDC, but as SUDEP. 
    Id.
     (citing Pet. Ex. 70 at 2).
    Further, Dr. Lidov opined that since N.A. did not have a history of prior seizures, and her
    “death [was] unwitnessed, [] the occurrence during a febrile seizure [was] only a supposition.”
    Resp. Ex. E at 5 (citing Pet. Ex. 70 at 2).
    Dr. Lidov also disagreed that the case report by Myers et al. was relevant, opining that
    the child’s death described in Myers et al. was not caused by a fatal febrile seizure but instead
    55
    Roger W. Byard, Sudden Death in the Young (3d ed. 2010). Three non-consecutive pages
    from this textbook were filed.
    56
    Shlomo Shinnar & Christine O’Dell, Febrile Seizures, 33 Pediatric Annals 395 (2004).
    57
    Shlomo Shinnar & Tracy A. Glauser, Febrile Seizures, 17 J. Child Neurology S44 (2002).
    58
    1 Shlomo Shinnar, Febrile Seizures, in Swaiman’s Pediatric Neurology 790 (Kenneth F.
    Swaiman et al. eds., 5th ed. 2012).
    59
    Maitreyi Mazumdar, Febrile Seizures and Risk of Death, 372 Lancet 429 (2008).
    60
    Alexander K.C. Leung & W. Lane M. Robson, Febrile Seizures, 21 J. Pediatric Health Care
    250 (2007).
    31
    reflected the child’s complex chromosomal abnormality. Tr. 119-20 (citing Pet. Ex. 71 at 1).
    The child had a chromosomal disorder with “dysmorphic features, bilateral cleft palate, short
    webbed neck, congenital heart disease . . . , and severe bilateral bronchomalacia.” Pet. Ex. 71 at
    3. Brain magnetic resonance imaging (“MRI”) was abnormal. 
    Id.
     She had “hypotonia from
    birth and global developmental delay.” 
    Id.
     Although the child presented to the hospital after
    febrile status epilepticus, she did not experience sudden death until two days later, during video
    EEG monitoring. 
    Id.
     The authors suggested that the physiologic changes prior to death may be
    similar to “some rare cases of adults who have experienced [SUDEP].” 
    Id. at 2
    . N.A. did not
    have epilepsy.
    Dr. Lidov was also not persuaded by Petitioners’ reliance on Crandall et al. Tr. 120
    (citing Pet. Ex. 72). There, the researchers collected interviews of family members who had
    voluntarily registered with the SUDC Foundation. 61 Pet. Ex. 72 at 2. In the SUDC group, 87 of
    241 (36.1%) reported a family history of febrile seizures, and 41 of 241 (17%) reported both a
    case and family history. 
    Id. at 5
    . Information was obtained from “[d]etailed demographic and
    interview histories.” 
    Id. at 4
    . “No independent medical record or autopsy review was
    performed.” 
    Id. at 3
    . Due to the lack of such more specific information, Dr. Lidov did not find
    the study persuasive. Tr. 120.
    On cross-examination, Dr. Lidov agreed that not all seizures are witnessed and some
    occur during sleep. Tr. 146-47. He also agreed that seizures can cause death, specifically
    generalized tonic-clonic seizures and focal seizures. Tr. 147, 156. He opined that the literature,
    specifically articles authored or co-authored by Dr. Kinney, hypothesizes that an unwitnessed
    seizure can cause SUDC. 
    Id.
     But he opined that articles related to SUDEP have only raised the
    possibility, which is “unproven,” that unwitnessed seizures can lead to death. Tr. 147-48.
    Regarding Petitioners’ assertion that the presence of hippocampal abnormalities is
    evidence that supports Petitioners’ theory, Dr. Lidov disagreed. Resp. Ex. E at 5-7; Resp. Ex. I
    at 13. Any association between febrile seizures and hippocampal abnormalities, according to Dr.
    Lidov, is not evidence of a causal mechanism. Resp. Ex. E at 4-5; Resp. Ex. I at 13. He
    explained that the literature noted an association, but never showed causality, despite Dr.
    Miller’s assertions. Resp. Ex. E at 5-7 (citing, e.g., Pet. Exs. 18, 26-29). Dr. Lidov contended
    that Petitioners are proposing a theory that “is at most ‘conceivable,’ or ‘cannot be proven to be
    utterly impossible.’” Resp. Ex. I at 13. Dr. Lidov found Dr. Kinney’s hypothesis that the
    mechanism in SUDC cases is an epilepsy-like mechanism may be plausible, but it is unproven.
    Tr. 157; see Pet. Ex. 29 at 13.
    Dr. Lidov agreed that a family history of febrile seizures is a risk factor for febrile
    seizures, but noted it is because of a genetic component. Tr. 139-40; see also Resp. Ex. E, Tab 7
    at 2 tbl.1 (noting first-degree relative with history of febrile seizures as a risk factor for first
    febrile seizure); Resp. Ex. E, Tab 4 at 2 (same). Even though a family history of febrile seizures
    increases the risk of having a febrile seizure, Dr. Lidov maintained “it [does not] make it a likely
    event.” Tr. 140; see also Resp. Ex. I at 13 (explaining “all children are at some risk,” but “this
    does not prove that [a seizure] occurred”).
    61
    Of note, Dr. Orrin Devinsky was a named author on this paper.
    32
    He opined that Petitioners suggest that a febrile seizure can cause death and relied upon
    literature noting an association of a family or personal history of febrile seizures with SUDC. Tr.
    144-45. He concluded that any association is not causal and in fact, a history of febrile seizure is
    a marker for a genetic abnormality. Tr. 145. And these genetic abnormalities can explain SUDC
    via a different mechanism. 
    Id.
    ii.     Althen Prongs Two and Three
    Dr. Lidov opined Petitioners’ theory was weak and unlikely here. Tr. 141; Resp. Ex. E at
    8-9. He found that more likely than not, N.A.’s vaccination was unrelated to her death. Resp.
    Ex. E at 9. Additionally, he found no evidence to support the assertion that more likely than not,
    N.A. died of a fatal first febrile seizure. Resp. Ex. I at 12.
    Dr. Lidov concluded there was “no evidence of a seizure, febrile or otherwise,” no
    evidence N.A. was febrile, and even if she was febrile, there was evidence that it was antecedent
    to her vaccination. Tr. 141-42. Next, he explained there is no literature to support a finding of a
    first fatal febrile seizure. Id.; see also Resp. Ex. I at 12. Moreover, the literature reports
    hippocampal abnormalities in children without a history of seizures. Tr. 142. He opined the
    probability of this factor of Petitioners’ theory was “more reasonable,” however, he found it was
    a “low probability of indicating seizures.” 
    Id.
     Lastly, he opined the MMRV vaccine “was not in
    any way responsible for [N.A.’s] death.” Tr. 144.
    Dr. Lidov opined there was no evidence that N.A. had a seizure at the time of her death
    for numerous reasons. Resp. Ex. E at 4; see also Tr. 117; Resp. Ex. I at 12-14; Resp. Ex. M at 1.
    First, N.A. had no history of seizures or any history of febrile responses following any previous
    vaccinations. Resp. Ex. E at 4. Second, there was no report of tongue biting on autopsy, despite
    evidence of deciduous dentition. 
    Id.
     He noted the lack of physical evidence (tongue biting,
    disrupted bed clothing) does not prove N.A. did not have a seizure, but would be strong evidence
    in favor of a seizure if this evidence was present. Tr. 117.
    Third, N.A. only had “a very low fever,” which “argues [] against the idea of [N.A.]
    having had a febrile seizure” because her temperature did not reach the threshold seen in fever-
    induced seizures. Tr. 117-18; see also Resp. Ex. E at 8 (noting a fever-induced seizure typically
    requires a significant fever of around 103°F); Resp. Ex. E, Tab 4 at 2 (“The most significant risk
    factor for the development of a first febrile seizure is the height of the temperature; the higher the
    temperature, the higher the likelihood of a febrile seizure.”). Because N.A. had experienced low-
    grade fevers prior to the night of June 30 but had never had a seizure, Dr. Lidov argued that it is
    “less likely” that N.A.’s response to the low-grade fever on June 30 would be a seizure. Tr. 140-
    41; see also Resp. Ex. E at 8. Additionally, because N.A. had low-grade fevers since June 19,
    prior to her MMRV vaccination, Dr. Lidov found “no basis for presuming her vaccination[]
    [was] a necessary cause.” Resp. Ex. E at 8.
    Fourth, Dr. Lidov did not find N.A.’s family history of febrile seizures in her brother to
    be persuasive evidence that she had a seizure. Tr. 118. Lastly, Dr. Lidov did not find the fact
    that N.A. was found in the prone position to be evidence that she died of a seizure. Tr. 138-39.
    33
    He found it indicated that N.A. was unconscious at the time of her death but did not provide
    evidence of the cause of death. Tr. 138-39, 156. Additionally, he asserted it could indicate other
    processes that result in the prone position. Tr. 155. Given Dr. Lidov’s experience, and his
    review of the literature, he found no evidence of a first febrile seizure being fatal. Tr. 123, 137,
    141-42.
    Dr. Lidov disagreed with Dr. Miller’s brain abnormality findings and opined “the autopsy
    brain slides were completely [] normal for her age.” Tr. 125; see also Resp. Ex. E at 3 (noting
    “the brain regions sampled show[ed] no definite or diagnostic abnormalities”); Resp. Ex. I at 2-
    12 (detailing his disagreements with Dr. Miller over the brain slides and findings); Resp. Ex. M
    at 1-2 (maintaining bilamination and dispersion were not present on N.A.’s slides). He found the
    photomicrographs “simply [did] not show bilamination at all and that there [were] no other
    abnormalities in the hippocampus.” Tr. 136; see also Resp. Ex. E at 8. He also found it
    “unclear” how cell loss in the inferior olivary bears on this case as it is not a source of seizures.
    Tr. 136.
    Specifically, Dr. Lidov found no evidence of a subtle depletion of the large neurons from
    each inferior olivary nucleus and no evidence of bilamination. Tr. 125; Resp. Ex. E at 3, 8. In
    his expert reports and during the hearing, Dr. Lidov detailed what a normal dentate gyrus and
    bilamination look like, relying on photographs from the literature, and using those, he explained
    why N.A. exhibited no hippocampal abnormalities. See Tr. 126-34; Resp. Ex. E at 3, 8; Resp.
    Ex. I at 5-9 (citing Pet. Exs. 26, 29; Resp. Ex. I, Tab 2; 62 Resp. Ex. I, Tab 5; 63 Resp. Ex. I, Tab
    8). 64 Dr. Lidov also detailed his findings as to the inferior olivary. See Tr. 136-37; Resp. Ex. I
    at 9-12.
    He opined that Dr. Miller’s photomicrographs of N.A.’s dentate gyrus were at a higher
    magnification and not the same magnification as the photographs in the literature. Tr. 134. By
    using a higher magnification, Dr. Lidov testified, “you can find areas like this in normal dentate
    gyruses and in dentate gyruses of children who’ve died of lots of different diseases.” 
    Id.
     He
    further explained that a close up, cropped photograph does not show the entire field. Tr. 135.
    Overall, he found Dr. Miller’s photomicrographs “not convincing for bilamination.” Id.; see also
    Resp. Ex. I at 12
    Further, in a supplemental report, Dr. Lidov noted “the significance attributed to the
    presence of hippocampal malformations may be moot” as recent studies have suggested such
    findings occur more frequently in the general population. Resp. Ex. M at 2; see, e.g., Resp. Ex.
    62
    Ingmar Blümcke et al., Towards a Clinico-Pathological Classification of Granule Cell
    Dispersion in Human Mesial Temporal Lobe Epilepsies, 117 Acta Neuropathology 535 (2009).
    63
    Carolyn R. Houser, Granule Cell Dispersion in the Dentate Gyrus of Humans with Temporal
    Lobe Epilepsy, 535 Brain Rsch. 195 (1990).
    64
    Alexandre Valoota da Silva et al., Dysmorphic Neurons in Patients with Temporal Lobe
    Epilepsy, 1072 Brain Rsch. 200 (2006).
    34
    K at 2; Resp. Ex. I, Tab 1 at 18. 65 Thus, “their presence or absence is of no established
    significance.” Resp. Ex. M at 2. He cited Dr. Miller’s first expert report, which stated,
    [f]or completeness I must point out that I and some colleagues here at the
    University of Missouri School of Medicine have been studying this very issue of
    dentate gyrus dysplasia, and we have found that it is very common in the general
    autopsy population at all ages and with all sorts of causes of death [].
    Pet. Ex. 22 at 7.
    Additionally, Dr. Lidov referenced the SUDCRRC investigation and the fact that they did
    not find any brain abnormality confirmed his opinions that N.A. did not have any brain
    abnormalities. Tr. 144. Dr. Lidov explained that the SUDCRRC neuropathologist would have
    focused on brain abnormalities, a focus of interest in their group. Tr. 154. Additionally, he
    testified that Dr. Devinsky, the principal investigator of the SUDCRRC report, is also an author
    in many of the articles filed herein on the subject of brain abnormalities in children. Tr. 153-55;
    see, e.g., Pet. Exs. 15, 72, 74.
    In summary, Dr. Lidov agreed that N.A. fell into the SUDC category. Tr. 138; Resp. Ex.
    E at 4. He opined that her death was unexplained, stating “[w]e do not understand why” N.A.
    died. Tr. 138. Speculative causes include genetic abnormalities and cardiac arrhythmia. Id.; see
    also Resp. Ex. I at 15. However, Dr. Lidov concluded that it is “very unlikely” that N.A. had a
    febrile seizure. Tr. 137. He disagreed that N.A. had any brain abnormalities. 
    Id.
     And he opined
    the literature does not support Petitioners’ theory that N.A. had a fatal febrile seizure. 
    Id.
     Lastly,
    Dr. Lidov opined that more likely than not, N.A.’s vaccination was unrelated to her death. Resp.
    Ex. E at 9.
    4.      Respondent’s Expert, Dr. Sara O. Vargas, M.D. 66
    a.      Background and Qualifications
    Dr. Vargas is a pathologist with board certifications in anatomic pathology, clinical
    pathology, and pediatric pathology. Resp. Ex. C at 2. She received her A.B. from Harvard
    University and an M.D. from the University of Vermont College of Medicine. Resp. Ex. Q at 1.
    She then completed a residency in anatomic and clinical pathology and fellowship in pulmonary
    pathology at Brigham and Women’s Hospital and a pediatric pathology fellowship at Children’s
    Hospital in Boston, Massachusetts. Id.; Tr. 161. Dr. Vargas is an associate professor at Harvard
    Medical School and a staff pathologist at Children’s Hospital and Brigham and Women’s
    Hospital. Resp. Ex. Q at 1-2; Resp. Ex. C at 2. As a pathologist, she “practice[s] surgical
    pathology, cytopathology, postmortem examinations, and consultative diagnostic services.”
    65
    Achira Roy et al., Hippocampal Granule Cell Dispersion: A Non-Specific Finding in Pediatric
    Patients with No History of Seizures, 8 Acta Neuropathologica Commc’ns 1 (2020).
    66
    Dr. Vargas submitted three expert reports and testified at the hearing. Resp. Exs. C, J, N; Tr.
    3.
    35
    Resp. Ex. C at 2. She also reviews autopsies for Robert’s Program, “a multidisciplinary group
    that investigates sudden unexpected death in infancy and in childhood,” similar to SUDCRRC.
    Tr. 164-65, 167. Dr. Vargas has authored or co-authored over 200 publications. Resp. Ex. Q at
    18-41.
    b.     Opinion
    Dr. Vargas opined N.A. “died of [SUDC] in the setting of a viral respiratory tract
    infection,” with “no evidence that immunizations caused, or contributed in any way to [] [N.A.’s]
    death.” Resp. Ex. C at 8; see also Resp. Ex. J at 1, 4.
    i.      Althen Prong One
    Dr. Vargas opined there is no evidence that vaccination can cause SUDC via a seizure.
    Tr. 168; Resp. Ex. J at 1-2 (finding “no evidence that vaccinations are associated with any
    increased risk of SIDS/SUDC or that they ‘potentiate’ SIDS/SUDC”). Dr. Vargas testified that
    certain vaccinations protect against forms of sudden death. Tr. 168. Varicella, for example,
    “protects against varicella and therefore protects against the fatal complication of that which can
    include fatal pneumonia, fatal superimposed bacterial pneumonia on a viral pneumonia, or
    sometimes from the skin lesions[] you can get a superimposed bacterial infection[] [] that can
    enter the bloodstream and cause death.” Tr. 168-69.
    Dr. Vargas also “disagree[d] strongly with [Petitioners’] theory that the large majority of
    SIDS and SUDC are caused by a seizure,” regardless of the presence of a hippocampal
    abnormality. Tr. 179. She opined that the hippocampal abnormality described in cases of SIDS,
    SUDC, and SUDEP “is a nonspecific finding” seen in many cases. Resp. Ex. J at 3; see also Tr.
    178-79. “Although it is present at increased rates in patients with epilepsy history, it is unclear
    whether the hippocampal malformation might be a cause of seizure, a consequence of seizure,
    two separate consequences of another abnormality (e.g., genetic), or other.” Resp. Ex. J at 3
    (citing Resp. Ex. J, Tab 5 at 8-9). 67 Additionally, she noted there is no evidence that such
    malformations “cause death, no evidence that fever induces them to cause death, nor any
    evidence that vaccination induces them to cause death.” 
    Id.
     Thus, Dr. Vargas argued the
    presence of a hippocampal abnormality does not automatically classify a case as SUDC without
    a cause or explanation. Tr. 178.
    In support of her opinions, Dr. Vargas cited several papers. McGuone et al. examined 20
    SUDC cases and found 12 had a history of febrile seizures, 85% died during apparent sleep, and
    80% were in the prone position. Resp. Ex. J, Tab 5 at 1. The authors concluded that any
    “significance and specificity of hippocampal findings [was] unclear” because abnormalities in
    the dentate gyrus were found in unexplained and explained deaths. 
    Id. at 1, 8-9
    . Thus, the
    “hippocampal findings may be a result of seizures, a contributor to seizures, an unrelated
    phenomenon, or a normal anatomic variant in children.” 
    Id. at 9
    .
    67
    Declan McGuone et al., Neuropathologic Changes in Sudden Unexplained Death in
    Childhood, 79 J. Neuropathology & Experimental Neurology 336 (2020).
    36
    Abdel-Mannan et al. 68 defined a definite case of SUDEP as “[s]udden, unexpected,
    witnessed or unwitnessed, non-traumatic and non-drowning death, occurring in benign
    circumstances, in an individual with epilepsy, with or without evidence for a seizure and
    excluding documented status epilepticus in which postmortem examination does not reveal a
    cause of death.” Resp. Ex. J, Tab 1 at 2. Dr. Vargas explained the mechanism of death in
    SUDEP is unknown. Resp. Ex. J at 3 (citing Resp. Ex. J, Tab 1 at 1). There is also no evidence
    that fevers can trigger SUDEP. 
    Id.
     Dr. Vargas explained that for SUDEP, it is postulated that
    abnormalities of ion channels in the brain and heart may render individuals predisposed to
    seizures and sudden cardiac arrest. 
    Id.
     (citing Resp. Ex. J, Tab 1 at 7).
    Dr. Vargas agreed the MMRV vaccination causes fevers and sometimes causes seizures,
    and this risk of seizure peaks at seven to 10 days post-vaccination. Tr. 181-82. When asked
    whether death could occur when “a child [] sleeping on the[ir] stomach [] [loses] consciousness
    due to a seizure,” Dr. Vargas testified “[p]robably.” Tr. 185. She explained, however, that death
    from a first febrile seizure is rare. Tr. 180.
    She also noted fevers caused by viral infections can trigger seizures. Tr. 184. And
    seizures can lead to injuries, such as tongue biting, falls, and a compromised respiratory tract due
    to aspiration of material. Tr. 184-85.
    ii.     Althen Prongs Two and Three
    Dr. Vargas agreed N.A.’s death is best classified as SUDC. Resp. Ex. C at 5; Resp. Ex. J
    at 4; Tr. 169. Although there are aspects of N.A.’s death that resemble SIDS, Dr. Vargas opined
    N.A.’s death does not qualify as SIDS. Resp. Ex. C at 5; see also Tr. 163-64 (testifying there is a
    “strict age cut-off” at “one year of age”). She also opined that N.A. did not have epilepsy or
    SUDEP, and even if she had a history of epilepsy, Dr. Vargas found no evidence that a vaccine-
    induced fever could have caused death in such scenario. Resp. Ex. J at 3.
    Next, Dr. Vargas opined that there is no evidence that N.A. had a febrile seizure. Resp.
    Ex. C at 6-7; Tr. 175. She noted N.A. had no history of seizures and no seizure was observed on
    the night of her death. Resp. Ex. C at 6. N.A.’s fevers around the time of her death were only
    “low-grade, lower than characteristically observed with febrile seizures.” Id.; see also Tr. 175-
    76. Additionally, Dr. Vargas found N.A.’s autopsy showed no evidence of seizure activity.
    Resp. Ex. C at 6. For example, there was no evidence of tongue-biting, which is a finding Dr.
    Vargas found typical with a suspected seizure. 
    Id. at 7
    . Dr. Vargas found “[t]he fact that the
    medical examiner did not describe or sample [N.A.’s] tongue may reflect a lack of any
    substantial degree of suspicion for seizure on the part of the medical examiner.” 
    Id.
    She disagreed with Petitioners’ experts’ arguments that a history of seizures in N.A.’s
    brother was evidence that N.A. had a seizure. Resp. Ex. C at 7. While Dr. Vargas agreed that
    “[s]eizures can be familial,” she disagreed that “[h]aving a single family member with seizures . .
    68
    Omar Abdel-Mannan et al., A Systematic Review of Sudden Unexpected Death in Epilepsy
    (SUDEP) in Childhood, 90 Epilepsy & Behavior 99 (2019).
    37
    . automatically confer[s] seizure susceptibility.” Tr. 176; Resp. Ex. C at 7. Additionally, N.A.
    did not exhibit a history of seizures or developmental issues that were seen in her brother. Resp.
    Ex. J at 2; Tr. 176-77. Thus, Dr. Vargas opined any link between N.A.’s death and her brother’s
    seizures “[was] tenuous at best” and “probably negligible.” Resp. Ex. J at 2; Tr. 177.
    Dr. Vargas questioned Dr. Kinsbourne’s opinions that “the configuration of the body in
    rigor mortis was unusual, less like an infant death by asphyxia than death during a seizure.”
    Resp. Ex. C at 7 (quoting Pet. Ex. 13 at 2). She responded that Dr. Kinsbourne “provide[d] no
    explanation for what was ‘unusual’ about the rigor mortis, or why the configuration would
    indicate death due to seizure.” 
    Id.
     Additionally, the autopsy did not mention a particular body
    configuration that was “unusual” and rigor mortis, as Dr. Vargas explained, “is a natural and
    expected phase of postmortem change, and it is not in any way an indication of seizure.” 
    Id.
    With regard to the prone position on death, Dr. Vargas agreed this position is a common
    position in patients with SIDS or SIDS-like death and “it supports some of the mechanisms . . .
    proposed in SIDS.” Tr. 176. And for the disagreement as to the presence of a hippocampal
    abnormality in N.A., Dr. Vargas noted the presence of such abnormality “[was] not critical to
    [her] opinion that [N.A.’s] death was not caused by vaccination nor by fever.” Resp. Ex. J at 3.
    Dr. Vargas reviewed the report from SUDCRRC. Resp. Ex. N at 1-2. She noted the
    SUDCRRC did not find vaccination, fever, or seizure to be a cause of N.A.’s death. 
    Id.
     The
    report concluded cause of death was unexplained sudden death with an undetermined manner of
    death. 
    Id.
     at 2 (citing Pet. Ex. 77 at 9). Additionally, SUDCRRC conducted a genetic analysis
    and identified no known or expected pathogenic variants. 69 
    Id.
     (citing Pet. Ex. 77 at 8); see also
    Pet. Ex. 80 (genetics report). Based on the lack of any genetic abnormalities, Dr. Vargas opined
    that N.A. “had a little low risk” of seizures given the fact that the SUDCRRC did not identify
    genetic susceptibility to seizures. Tr. 177.
    Regarding the autopsy, Dr. Vargas reviewed the 12 autopsy slides and had several
    opinions. 70 Resp. Ex. C at 3-6; Tr. 171-72. First, she opined that there were no pathologic
    features shown in the heart tissue. Resp. Ex. C at 4.
    Second, Dr. Vargas found some of N.A.’s organs weighed more than what would be
    expected in a child N.A.’s age. Resp. Ex. C at 3 (citing Resp. Ex. C, Tab 1). 71 She noted that
    the lungs stood out as heavy compared to other organs. 
    Id. at 5-6
    ; Tr. 172. Dr. Vargas agreed
    69
    Dr. Vargas hypothesized the role of genetics in N.A.’s death in an expert report, prior to the
    filing of the genetic testing results from SUDCRRC. See Resp. Ex. J at 1-2.
    70
    For Dr. Vargas’ findings on the microscopic slides, see Resp. Ex. C at 4.
    71
    J.M. Coppoletta & S.B. Wolbach, Body Length and Organ Weights of Infants and Children: A
    Study of the Body Length and Normal Weights of the More Important Vital Organs of the Body
    Between Birth and Twelve Years of Age, 9 Am. J. Pathology 55 (1933). Only one chart from
    the article was filed.
    38
    with the medical examiner that there was inflammation in the submucosa of the upper airway but
    opined the inflammation chronic, not minimal, because it was well developed and lymphoid
    follicles were seen. Tr. 171. She also testified there was inflammation in the lower respiratory
    tract in the lungs with mild expanded lymphoid tissue. Tr. 172. Additionally, she agreed with
    the medical examiner’s finding of scatter macrophages in the alveoli; however, she did not find
    pulmonary edema present. Tr. 172, 188-89.
    Based on the autopsy and other evidence, Dr. Vargas opined it was “unlikely that
    ‘asphyxia’ described the cause of death accurately or fully.” Resp. Ex. C at 5. She explained
    “[a]sphyxia, by definition, indicated a lack of oxygen,” and “[w]hen death is attributed to
    ‘asphyxia’ it usually indicated a blockage of air [] by a physical object.” 
    Id.
     “[N]atural diseases
    [] may lead to a deficiency of oxygen as the mechanism of death,” but the term “asphyxia” is not
    applied. 
    Id.
     She opined N.A. “had no obvious entanglement in bedding, no unsafe co-sleeping
    arrangement, and no apparent foul play to indicate asphyxiation as a sole cause of death.” 
    Id.
    She also agreed healthy one-year-olds “are expected to be able to turn their heads during periods
    of sleep to avoid suffocation.” 
    Id.
    Regarding the cause of death, Dr. Vargas testified that there were many possible causes
    of death, including occult infection, cardiac arrhythmia, and failure to autoresuscitate. Tr. 180.
    On cross-examination, Dr. Vargas noted that these possible causes of N.A.’s death did not reach
    the level of more likely than not. Tr. 182-83. However, she opined that each were more likely to
    cause death than a febrile seizure. Tr. 185-86.
    Dr. Vargas opined that “the most likely explanation for [N.A.’s] fevers was a virus.”
    Resp. Ex. C at 5; see also Resp. Ex. J at 3. N.A. had low-grade fever beginning on June 19,
    2016, which pre-dated her MMRV vaccination on June 23, 2016, and thus, it could not have
    been caused by vaccination. Resp. Ex. C at 5 (citing Pet. Ex. 5 at 5); Tr. 174; Resp. Ex. J at 3.
    Dr. Vargas opined N.A. had “chronic lymphoplasmacytic inflammation involving the respiratory
    tract observed at autopsy.” Resp. Ex. C at 5; see also Resp. Ex. J at 3. She stressed that the
    respiratory tract inflammation involved both the lower and upper respiratory tract. Resp. Ex. J at
    4. Given these findings, Dr. Vargas opined N.A. had a respiratory tract viral infection. 
    Id. at 3
    ;
    Resp. Ex. C at 5; Tr. 172-73. Additionally, N.A.’s twin sister, L.A., had a low-grade fever on
    July 1, 2016, and a viral cause would be “a likely possibility.” Resp. Ex. C at 6 (citing Pet. Ex. 7
    at 5 (noting “viral illness” as a differential diagnosis)). She opined that this “could indicate that
    [L.A.] had whatever viral infection that N.A. had.” Tr. 175; see also Resp. Ex. J at 4.
    Dr. Vargas explained “[v]iruses with a predilection for the pediatric respiratory tract
    include rhinoviruses, respiratory syncytial virus, adenoviruses, influenza viruses, parainfluenza
    viruses, human bocavirus, and human metapneumovirus” and “[i]nfection with respiratory
    viruses is exceedingly common in children.” Resp. Ex. C at 5. Although there were “no reports
    39
    of any viral testing conducted as a part of [N.A.’s] autopsy, nor of any bacterial testing,” 72 Dr.
    Vargas opined “[i]t is expected that had comprehensive testing for viral respiratory pathogens
    been conducted, it would have likely confirmed viral infection.” 
    Id. at 5-6
    . She added that a
    virus would explain the chronic inflammation seen in N.A.’s upper and lower respiratory tract
    and could have caused concomitant chronic inflammation in other organs. 
    Id. at 6
    . She
    concluded that such respiratory tract inflammation could not be explained by a vaccination. 
    Id. at 6
    . During the hearing, Dr. Vargas testified that a viral cause of N.A.’s death remained a
    “possibility.” Tr. 183.
    Dr. Vargas also posited that there could have been a bacterial cause of N.A.’s death.
    Resp. Ex. C at 6; Tr. 186. N.A. had cellulitis in her eye six weeks prior to her death. Resp. Ex.
    C at 6. Dr. Vargas noted various causes of cellulitis and opined that “these bacteria can spread
    through the body hematogenously and seed other sites.” 
    Id.
     Additionally, “[o]ccult abscesses
    and other bacterial infections can be associated with intermittent and persistent fevers, such as
    was observed in [N.A.].” 
    Id.
     Dr. Vargas opined it was “possible that the bacterial infection was
    not fully cured and seated somewhere or had a pocket left and could have been a source of
    infection . . . rather than the respiratory tract.” Tr. 186. Dr. Vargas acknowledged no anatomic
    sources of infection were identified during autopsy but explained that only a small proportion of
    N.A.’s tissue was sampled, making it difficult to rule out infection in other unsampled areas.
    Resp. Ex. C at 6; Tr. 183-84. Here, the cellulitis predated N.A.’s MMRV vaccination, and thus,
    it would preclude causation. Resp. Ex. C at 6. At the hearing, Dr. Vargas agreed that cellulitis
    or bacterial infection as a cause of death was only a “possibility.” Tr. 182-84, 186.
    5.      Respondent’s Expert, Dr. Christine McCusker, M.D. 73
    a.      Background and Qualifications
    Dr. McCusker received a B.Sc. in microbiology and immunology, M.Sc. in molecular
    biology, and M.D. in Ontario, Canada. Resp. Ex. A at 1; Resp. Ex. O at 1. She then completed a
    pediatric residency, fellowship in immunology, and a fellowship in allergy and immunology.
    Resp. Ex. O at 2. She obtained board certification from the American Board of Pediatrics and is
    certified in pediatrics and allergy and clinical immunology in Canada. Id.; Resp. Ex. A at 1. Dr.
    McCusker’s “research focus is the regulation of the immune responses.” Resp. Ex. A at 1. She
    treats an average of 50-120 children per week in allergy and clinical immunology as well as
    urgent care general pediatrics. 
    Id. at 2
    . Throughout her career, she has held various university
    72
    Dr. Vargas noted “[a] typical autopsy workup in unexpected death includes postmortem
    microbiologic culture for bacteria.” Resp. Ex. C at 6 (citing Resp. Ex. C, Tab 2 (Johan J.
    Dempers et al., The Institution of a Standardized Investigation Protocol for Sudden Infant Death
    in the Eastern Metropole, Cape Town, South Africa, 61 J. Forensic Scis. 1508 (2016))). She
    found it “striking . . . that there [was] no record of any postmortem microbiologic testing.” 
    Id.
    73
    Dr. McCusker submitted two expert reports and testified at the hearing. Resp. Exs. A, H; Tr.
    3. Dr. McCusker’s expert reports address theories from Dr. Miller that he abandoned at the
    hearing, and thus, the undersigned addresses only those opinions from Dr. McCusker that are
    relevant to this case and Petitioners’ theory.
    40
    and hospital appointments and she has authored or co-authored over 100 publications. Resp. Ex.
    O at 3-4, 33-46.
    b.      Opinion
    i.     Althen Prong One
    Dr. McCusker addressed Petitioners’ theory that N.A. suffered her first febrile seizure on
    the night of her death and this seizure was vaccine-induced. Resp. Ex. A at 9. Dr. McCusker
    noted Petitioners relied upon Kinney et al. (2009), which found 19 of the 49 SUDC cases had a
    family or personal history of febrile seizures. 
    Id.
     (citing Pet. Ex. 18 at 10 tbl.1). She explained
    that the incidence of febrile seizure or family history of febrile seizures “was not significantly
    different from controls in this study.” 
    Id.
     (citing Pet. Ex. 18 at 10 tbl.1). Additionally, Kinney et
    al. studied the frequency of hippocampal and temporal lobe abnormalities; however, only a small
    number amount of children’s hippocampus and temporal lobes were available for examination
    and some “frequencies were not statistically different.” 
    Id.
     Lastly, Dr. McCusker noted
    vaccination was not listed as a risk factor in Kinney et al. 
    Id.
    Dr. McCusker testified that “there is an increased risk of febrile seizures in family
    members of those who’ve had febrile seizures,” although the literature is “not particularly
    strong.” Tr. 210. She briefly discussed Hesdorffer et al. and Hefti et al., articles relied upon by
    Petitioners, and argued that these articles did not find a family history of febrile seizures was
    significantly increased in SUDC cases, with or without hippocampal abnormalities. Resp. Ex. A
    at 10 (citing Pet. Exs. 16, 27-28). She determined that an increased risk of febrile seizures in
    family members “would imply that there are genetic causes of the febrile seizures.” Tr. 210.
    Next, she explained that there are many similarities in the risk factors for death in SIDS
    and SUDC cases, including the prone sleeping position and infection or illness, although “an
    upper respiratory tract infection is considered a risk factor for [SIDS]” and “less so” for SUDC.
    Tr. 196; see also Resp. Ex. H at 1; Resp. Ex. A, Tab 27 at 3, 3 tbl.1 (noting prone position and
    mild infections as risk factors for SIDS); 74 Pet. Ex. 18 at 7, 10 tbl.1 (analyzing similarities in
    SUDC and non-SUDC cases); Pet. Ex. 16 at 7 tbl.2 (listing risk factors for SIDS, SUDC, febrile
    seizures, and SUDEP); Pet. Ex. 34 at 14 (“Mild infection around the time of death is present in
    approximately one-half of SIDS infants.”). 75 Kinney et al. explained that because these risk
    factors are not found in all cases, they “are not causative.” Resp. Ex. A, Tab 27 at 3.
    Vaccination was not listed as a risk factor. Resp. Ex. H at 2; see, e.g., Pet. Exs. 16, 18; Resp. Ex.
    A, Tab 27.
    74
    Hannah C. Kinney & Bradley T. Thach et al., Sudden Infant Death Syndrome, 
    361 New Eng. J. Med. 795
     (2009).
    75
    Hannah C. Kinney et al., The Serotonergic Anatomy of the Developing Human Medulla
    Oblongata: Implications for Pediatric Disorders of Homeostasis, 41 J. Chem. Neuroanatomy 182
    (2011).
    41
    At the hearing, Dr. McCusker explained that theoretically the prone position is a risk
    factor due to an infant’s inability to lift and turn their head, which can lead to an obstructed
    airway in the bedding or other item in the crib. Tr. 197-98; see also Resp. Ex. A at 13; Resp. Ex.
    A, Tab 27 at 4, 7. A child (over the age of one) engages in “resistive breathing,” where
    abdominal muscles are used to breathe and the stomach pushes out while breathing. Tr. 198.
    Thus, when a child is in the prone position, there is more effort engaged to breathe. 
    Id.
     Dr.
    McCusker contended that if a child has an upper respiratory infection with an obstructed airway,
    the prone position can result in a child that is unable to breathe. Tr. 199.
    Dr. McCusker cited various articles discussing airway obstruction in SIDS/SUDC and in
    the presence of upper respiratory infections. Resp. Ex. A at 13-15. She opined that upper
    respiratory tract infections in infants can cause upper airway obstructions, compromising airway
    function. 
    Id. at 15
    ; Resp. Ex. H at 2. And unlike vaccination, an upper respiratory tract
    infections “is a defined risk factor for SIDS, SUDC[,] and SUDEP.” Resp. Ex. H at 2.
    Bollag 76 explained “[i]nfants and small children have narrow airways,” and thus,
    “[i]nflammation and congestion of the mucosa can result in obstruction very rapidly.” Resp. Ex.
    A, Tab 37 at 1. Children up to the age of two have difficulty when both breathing and feeding
    through the mouth. 
    Id.
     Infants breathe through their nose and learn to breathe through their
    mouth during their first year of life. Resp. Ex. H at 2; see also Resp. Ex. A, Tab 33 at 4; 77 Resp.
    Ex. A, Tab 38 at 1. 78 Moschino et al. suggested that mucus in upper airways can affect
    respiratory functions. Resp. Ex. A, Tab 38 at 1. deAlmeida et al. 79 noted “[t]he switch to oral
    breathing in response to a nasal obstruction is crucial for survival, and has been put forward as an
    important mechanism in preventing [SIDS].” Resp. Ex. A, Tab 36 at 1; see also, e.g., Resp. Ex.
    G, Tab 1 at 1 (“It has [] been suggested that blockage of the nasal passages of infants who are
    obligate nose breathers could result in asphyxia and SIDS. In some infants, nasal obstruction
    may lead to pharyngeal closure, which may prolong an apnoeic period and exacerbate associated
    hypoxaemia.” (internal citations omitted)). 80
    76
    Ueli Bollag, Acute Respiration Infections in Childhood: Tackling the Problem at the Level of
    the Nose, 35 J. Tropical Pediatrics 140 (1989).
    77
    W.J. Kleemann et al., Infections of the Upper Respiratory Tract in Cases of Sudden Infant
    Death, 108 Int’l J. Legal Med. 85 (1995).
    78
    L. Moschino et al., Is Nasal Suctioning Warranted Before Measuring 02 Saturation in Infants
    with Bronchiolitis?, 101 Archives Disease Childhood 114 (2016).
    79
    Victor L. deAlmeida et al., The Effect of Nasal Occlusion on the Initiation of Oral Breathing
    in Preterm Infants, 18 Pediatric Pulmonology 374 (1994).
    80
    Richard Harding et al., Postnatal Development of Responses to Airflow Obstruction, 22
    Clinical & Experimental Pharmacology & Physiology 537 (1995).
    42
    Ralston et al., 81 a clinical practice guideline from the American Academy of Pediatrics,
    discussed frequent respiratory infections in children and recognized that an upper airway
    obstruction due to infection can increase the effort of breathing. Resp. Ex. A, Tab 31 at 6.
    Kleemann et al. compared nasal cavities in SIDS cases to control cases, all under the age of one,
    and determined rhinitis 82 “seem[ed] to be merely a result of the high incidence of upper
    respiratory tract infections in this age group.” Resp. Ex. A, Tab 33 at 1. The authors
    “speculate[d] [] that infections of the nose combined with other factors could play a role in []
    [SIDS].” 
    Id. at 4
    . The authors concluded that since infants breathe through their nose and learn
    to breathe through their mouth during their first year, “even small infections of the nose can
    cause obstruction of the airway.” 
    Id.
    ii.    Althen Prongs Two and Three
    Dr. McCusker found Petitioners’ theory “exceedingly unlikely.” Tr. 213. Dr. McCusker
    could not discern how N.A. died. 
    Id.
     But she found it “highly unlikely that the MMR[V]
    vaccine played a role in [N.A.’s] death.” 
    Id.
     She explained that even if seizures post-MMRV
    vaccine occur, “there is no increased frequency of infant death or SUDC in children who receive
    their MMRV.” Tr. 213-14. This “sequence of events” from Petitioners “simply doesn’t occur in
    the children who are at risk for febrile seizures who develop febrile seizures post-MMRV.” Tr.
    214.
    Dr. McCusker classified N.A.’s case as SUDC. Tr. 195. N.A. was described as having
    her feet sticking through the slacks of the crib upon discovery, which Dr. McCusker believed
    made it difficult for her to roll over. Tr. 200. She found this prone position increased the
    possibility of SUDC. Resp. Ex. A at 16; Resp. Ex. H at 3.
    Dr. McCusker acknowledged that N.A. was on day seven post-vaccination and was
    therefore within the risk period of febrile seizures post-MMRV vaccine. Resp. Ex. A at 9, 15;
    Resp. Ex. H at 3. She noted, however, that even though Petitioners’ studies showed febrile
    seizures occur at an increased frequency seven to 10 days following MMRV vaccination, these
    studied failed to mention an increased frequency of death (or SUDEP) during this time period.
    Resp. Ex. A at 9, 15; Resp. Ex. H at 3.
    Given the time of death from the medical examiner (between 9:00 p.m. and 10:00 p.m. on
    the night of June 30, 2016), and N.A.’s receipt of Motrin around 7:00 p.m. the night of June 30,
    2016, Dr. McCusker testified that the Motrin “would have been working” at the time of death
    since it is effective for eight hours. Tr. 211-12. Thus, she opined that N.A. would not have had a
    fever during this time. Tr. 213. And “any fever she had at that time prior to the [Motrin] would
    81
    Shawn L. Ralston et al., Clinical Practice Guideline: The Diagnosis, Management, and
    Prevention of Bronchiolitis, 134 Pediatrics e1474 (2014).
    82
    Rhinitis is “inflammation of the mucous membrane of the nose.” Rhinitis, Dorland’s Med.
    Dictionary Online, https://www.dorlandsonline.com/dorland/definition?id=43725 (last visited
    Nov. 13, 2023).
    43
    have been controlled during the time of her demise, suggesting . . . [a] fever-inducing seizure
    would be unlikely.” Tr. 211.
    With regard to the significance of family history of febrile seizures, Dr. McCusker opined
    that N.A.’s brother with a history of febrile seizures also has a genetic abnormality, a
    microdeletion in an area associated with neurodevelopmental delays. Tr. 210-11. Based on this,
    Dr. McCusker opined N.A.’s brother is not at the same “genetic standpoint” as N.A. Tr. 211.
    She explained that “the familial febrile seizures would not be predicted to be the same risks if the
    microdeletion is responsible for his . . . susceptibility to febrile seizures.” 
    Id.
    Dr. McCusker opined N.A. had a viral respiratory infection, which is a risk factor for
    SIDS and SUDC, for the following reasons. Tr. 200; Resp. Ex. A at 15; Resp. Ex. H at 2-3.
    First, N.A.’s autopsy revealed small amount of mucous in her nares, trachea, and bronchi and the
    respiratory mucosa was mildly congested. Tr. 200; Resp. Ex. A at 15 (citing Pet. Ex. 6 at 4). Dr.
    McCusker also relied upon Dr. Vargas’ findings here as it relates to the pathology. Tr. 200. She
    noted N.A. had a runny nose on the day she died. 
    Id.
     Although N.A. was noted to be feeling
    warm on the night of her death, Dr. McCusker found no evidence N.A. had a fever. Resp. Ex. H
    at 2. She maintained N.A.’s autopsy findings can be “reasonably [] attributed” to an upper
    respiratory tract infection. 
    Id.
     And at the hearing, she noted that there are explanations other
    than vaccination for why a child would develop a fever. Tr. 202-04 (citing Resp. Ex. V). 83
    Additionally, N.A.’s twin sister, L.A., went to the hospital following N.A.’s passing and
    “was diagnosed with crusting in the nose and what was felt to be a[n] acute viral infection.” Tr.
    200; see also Resp. Ex. A at 15. N.A.’s brother was diagnosed with an infection 16 days after
    N.A.’s death, which Dr. McCusker found suggested an acute viral illness was circulating in the
    family on the night of N.A.’s death. Resp. Ex. A at 15. Given these facts, she concluded that
    “[i]t [was] possible . . . that [N.A.] may also have had an undiagnosed upper respiratory tract
    infection leading to airway occlusion in the prone position as suggested by Kinney et al.” 
    Id.
    (citing Pet. Ex. 18); see also Resp. Ex. H at 2.
    Dr. McCusker opined that any congestion N.A. had would not have been caused by her
    MMRV vaccination. Tr. 201. She agreed MMRV vaccination can trigger a fever but “runny
    nose and crusting of the nose is not a feature of MMRV.” 
    Id.
    She acknowledged that a finding of an upper respiratory infection would be insufficient
    to cause asphyxia, but argued that an upper respiratory tract infection can cause upper airway
    obstruction and, unlike vaccination, an upper respiratory tract infection “is a defined risk factor
    for SIDS, SUDC[,] and SUDEP.” Resp. Ex. H at 2.
    Dr. McCusker concluded that N.A. likely had an acute infection at the time of death.
    Resp. Ex. A at 16; Resp. Ex. H at 2-3. She found no evidence supporting a mechanistic role for
    MMRV vaccination in N.A.’s death. Resp. Ex. A at 16; Resp. Ex. H at 3.
    83
    Caroline Hervé et al., The How’s and What’s of Vaccine Reactogenicity, 39 NPJ Vaccines 1
    (2019).
    44
    IV.    DISCUSSION
    A.      Standards for Adjudication
    The Vaccine Act was established to compensate vaccine-related injuries and deaths. §
    10(a). “Congress designed the Vaccine Program to supplement the state law civil tort system as
    a simple, fair and expeditious means for compensating vaccine-related injured persons. The
    Program was established to award ‘vaccine-injured persons quickly, easily, and with certainty
    and generosity.’” Rooks v. Sec’y of Health & Hum. Servs., 
    35 Fed. Cl. 1
    , 7 (1996) (quoting
    H.R. Rep. No. 908 at 3, reprinted in 1986 U.S.C.C.A.N. at 6287, 6344).
    Petitioners’ burden of proof is by a preponderance of the evidence. § 13(a)(1). The
    preponderance standard requires a petitioner to demonstrate that it is more likely than not that the
    vaccine at issue caused the injury. Moberly v. Sec’y of Health & Hum. Servs., 
    592 F.3d 1315
    ,
    1322 n.2 (Fed. Cir. 2010). Proof of medical certainty is not required. Bunting v. Sec’y of Health
    & Hum. Servs., 
    931 F.2d 867
    , 873 (Fed. Cir. 1991). Petitioners need not make a specific type of
    evidentiary showing, i.e., “epidemiologic studies, rechallenge, the presence of pathological
    markers or genetic predisposition, or general acceptance in the scientific or medical communities
    to establish a logical sequence of cause and effect.” Capizzano v. Sec’y of Health & Hum.
    Servs., 
    440 F.3d 1317
    , 1325 (Fed. Cir. 2006). Instead, Petitioners may satisfy their burden by
    presenting circumstantial evidence and reliable medical opinions. 
    Id. at 1325-26
    .
    In particular, Petitioners must prove that the vaccine was “not only [the] but-for cause of
    the injury but also a substantial factor in bringing about the injury.” Moberly, 
    592 F.3d at 1321
    (quoting Shyface v. Sec’y of Health & Hum. Servs., 
    165 F.3d 1344
    , 1352-53 (Fed. Cir. 1999));
    see also Pafford v. Sec’y of Health & Hum. Servs., 
    451 F.3d 1352
    , 1355 (Fed. Cir. 2006). The
    received vaccine, however, need not be the predominant cause of the injury. Shyface, 
    165 F.3d at 1351
    . A petitioner who satisfies this burden is entitled to compensation unless Respondent
    can prove, by a preponderance of the evidence, that the vaccinee’s injury is “due to factors
    unrelated to the administration of the vaccine.” § 13(a)(1)(B). However, if a petitioner fails to
    establish a prima facie case, the burden does not shift. Bradley v. Sec’y of Health & Hum.
    Servs., 
    991 F.2d 1570
    , 1575 (Fed. Cir. 1993).
    “Regardless of whether the burden ever shifts to the [R]espondent, the special master
    may consider the evidence presented by the [R]espondent in determining whether the [P]etitioner
    has established a prima facie case.” Flores v. Sec’y of Health & Hum. Servs., 
    115 Fed. Cl. 157
    ,
    162-63 (2014); see also Stone v. Sec’y of Health & Hum. Servs., 
    676 F.3d 1373
    , 1379 (Fed. Cir.
    2012) (“[E]vidence of other possible sources of injury can be relevant not only to the ‘factors
    unrelated’ defense, but also to whether a prima facie showing has been made that the vaccine
    was a substantial factor in causing the injury in question.”); de Bazan v. Sec’y of Health & Hum.
    Servs., 
    539 F.3d 1347
    , 1353 (Fed. Cir. 2008) (“The government, like any defendant, is permitted
    to offer evidence to demonstrate the inadequacy of the [P]etitioner’s evidence on a requisite
    element of the [P]etitioner’s case-in-chief.”); Pafford, 451 F.3d at 1358-59 (“[T]he presence of
    multiple potential causative agents makes it difficult to attribute ‘but for’ causation to the
    vaccination. . . . [T]he Special Master properly introduced the presence of the other unrelated
    contemporaneous events as just as likely to have been the triggering event as the vaccinations.”).
    45
    B.     Factual Issues
    Petitioners must prove, by a preponderance of the evidence, the factual circumstances
    surrounding their claim. § 13(a)(1)(A). To resolve factual issues, the special master must weigh
    the evidence presented, which may include contemporaneous medical records and testimony.
    See Burns v. Sec’y of Health & Hum. Servs., 
    3 F.3d 415
    , 417 (Fed. Cir. 1993) (explaining that a
    special master must decide what weight to give evidence including oral testimony and
    contemporaneous medical records).
    Medical records, specifically contemporaneous medical records, are presumed to be
    accurate and generally “warrant consideration as trustworthy evidence.” Cucuras v. Sec’y of
    Health & Hum. Servs., 
    993 F.2d 1525
    , 1528 (Fed. Cir. 1993). But see Kirby v. Sec’y of Health
    & Hum. Servs., 
    997 F.3d 1378
    , 1382 (Fed. Cir. 2021) (rejecting the presumption that “medical
    records are accurate and complete as to all the patient’s physical conditions”); Shapiro v. Sec’y
    of Health & Hum. Servs., 
    101 Fed. Cl. 532
    , 538 (2011) (“[T]he absence of a reference to a
    condition or circumstance is much less significant than a reference which negates the existence
    of the condition or circumstance.” (quoting Murphy v. Sec’y of Health & Hum. Servs., 
    23 Cl. Ct. 726
    , 733 (1991), aff’d per curiam, 
    968 F.2d 1226
     (Fed. Cir. 1992))), recons. den’d after remand,
    
    105 Fed. Cl. 353
     (2012), aff’d mem., 
    503 F. App’x 952
     (Fed. Cir. 2013). The weight afforded to
    contemporaneous records is due to the fact that they “contain information supplied to or by
    health professionals to facilitate diagnosis and treatment of medical conditions. With proper
    treatment hanging in the balance, accuracy has an extra premium.” 
    Id.
     To overcome the
    presumptive accuracy of medical records, a petitioner may present testimony which is
    “consistent, clear, cogent, and compelling.” Sanchez v. Sec’y of Health & Hum. Servs., No. 11-
    685V, 
    2013 WL 1880825
    , at *3 (Fed. Cl. Spec. Mstr. Apr. 10, 2013) (citing Blutstein v. Sec’y of
    Health & Hum. Servs., No. 90-2808V, 
    1998 WL 408611
    , at *5 (Fed. Cl. Spec. Mstr. June 30,
    1998)), mot. for rev. denied, 
    142 Fed. Cl. 247
     (2019), vacated on other grounds & remanded, 
    809 F. App’x 843
     (Fed Cir. 2020).
    There are situations in which compelling testimony may be more persuasive than written
    records, such as where records are deemed to be incomplete or inaccurate. Campbell v. Sec’y of
    Health & Hum. Servs., 
    69 Fed. Cl. 775
    , 779 (2006) (“[L]ike any norm based upon common
    sense and experience, this rule should not be treated as an absolute and must yield where the
    factual predicates for its application are weak or lacking.”); Lowrie v. Sec’y of Health & Hum.
    Servs., No. 03-1585V, 
    2005 WL 6117475
    , at *19 (Fed. Cl. Spec. Mstr. Dec. 12, 2005)
    (“[W]ritten records which are, themselves, inconsistent, should be accorded less deference than
    those which are internally consistent.” (quoting Murphy, 
    23 Cl. Ct. at 733
    ). Ultimately, a
    determination regarding a witness’s credibility is needed when determining the weight that such
    testimony should be afforded. Andreu v. Sec’y of Health & Hum. Servs., 
    569 F.3d 1367
    , 1379
    (Fed. Cir. 2009); Bradley, 991 F.2d at 1575.
    Despite the weight afforded medical records, special masters are not bound rigidly by
    those records in determining onset of a petitioner’s symptoms. Valenzuela v. Sec’y of Health &
    Hum. Servs., No. 90-1002V, 
    1991 WL 182241
    , at *3 (Fed. Cl. Spec. Mstr. Aug. 30, 1991); see
    also Eng v. Sec’y of Health & Hum. Servs., No. 90-1754V, 
    1994 WL 67704
    , at *3 (Fed. Cl.
    46
    Spec. Mstr. Feb. 18, 1994) (Section 13(b)(2) “must be construed so as to give effect also to §
    13(b)(1) which directs the special master or court to consider the medical records (reports,
    diagnosis, conclusions, medical judgment, test reports, etc.), but does not require the special
    master or court to be bound by them”).
    C.      Causation
    To receive compensation through the Program, Petitioners must prove either (1) that N.A.
    suffered a “Table Injury”—i.e., an injury listed on the Vaccine Injury Table—corresponding to a
    vaccine that she received, or (2) that N.A. suffered an injury that was actually caused by a
    vaccination. See §§ 11(c)(1), 13(a)(1)(A); Capizzano, 
    440 F.3d at 1319-20
    . Petitioners must
    show that the vaccine was “not only a but-for cause of the injury but also a substantial factor in
    bringing about the injury.” Moberly, 
    592 F.3d at 1321
     (quoting Shyface, 
    165 F.3d at 1352-53
    ).
    Because Petitioners do not allege N.A. suffered a Table Injury, they must prove a vaccine
    N.A. received caused her injury. To do so, Petitioners must establish, by preponderant evidence:
    “(1) a medical theory causally connecting the vaccination and the injury; (2) a logical sequence
    of cause and effect showing that the vaccination was the reason for the injury; and (3) a showing
    of a proximate temporal relationship between vaccination and injury.” Althen, 
    418 F.3d at 1278
    .
    The causation theory must relate to the injury alleged. Petitioners must provide a sound
    and reliable medical or scientific explanation that pertains specifically to this case, although the
    explanation need only be “legally probable, not medically or scientifically certain.” Knudsen v.
    Sec’y of Health & Hum. Servs., 
    35 F.3d. 543
    , 548-49 (Fed. Cir. 1994). Petitioners cannot
    establish entitlement to compensation based solely on their assertions; rather, a vaccine claim
    must be supported either by medical records or by the opinion of a medical doctor. § 13(a)(1).
    In determining whether a petitioner is entitled to compensation, the special master shall consider
    all material in the record, including “any . . . conclusion, [or] medical judgment . . . which is
    contained in the record regarding . . . causation.” § 13(b)(1)(A). The undersigned must weigh
    the submitted evidence and the testimony of the parties’ proffered experts and rule in Petitioners’
    favor when the evidence weighs in their favor. See Moberly, 
    592 F.3d at 1325-26
     (“Finders of
    fact are entitled—indeed, expected—to make determinations as to the reliability of the evidence
    presented to them and, if appropriate, as to the credibility of the persons presenting that
    evidence.”); Althen, 
    418 F.3d at 1280
     (noting that “close calls” are resolved in a petitioner’s
    favor).
    Testimony that merely expresses the possibility—not the probability—is insufficient, by
    itself, to substantiate a claim that such an injury occurred. See Waterman v. Sec’y of Health &
    Hum. Servs., 
    123 Fed. Cl. 564
    , 573-74 (2015) (denying a petitioner’s motion for review and
    noting that a possible causal link was not sufficient to meet the preponderance standard). The
    Federal Circuit has made clear that the mere possibility of a link between a vaccination and a
    petitioner’s injury is not sufficient to satisfy the preponderance standard. Moberly, 
    592 F.3d at 1322
     (emphasizing that “proof of a ‘plausible’ or ‘possible’ causal link between the vaccine and
    the injury” does not equate to proof of causation by a preponderance of the evidence); Boatmon
    v. Sec’y of Health & Hum. Servs., 
    941 F.3d 1351
    , 1359-60 (Fed. Cir. 2019). While certainty is
    47
    by no means required, a possible mechanism does not rise to the level of preponderance.
    Moberly, 
    592 F.3d at 1322
    ; see also de Bazan, 
    539 F.3d at 1351
    .
    V.       FACTUAL ANALYSIS
    As Federal Circuit precedent establishes, in certain cases it is appropriate to determine the
    nature of an injury before engaging in the Althen analysis. Broekelschen v. Sec’y of Health &
    Hum. Servs., 
    618 F.3d 1339
    , 1346 (Fed. Cir. 2010). Since “each prong of the Althen test is
    decided relative to the injury[,]” determining facts relating to the claimed injury can be
    significant. 
    Id.
     Here, the parties have identified two factual issues. First, they dispute whether
    N.A. suffered a seizure during the night of June 30, 2016 or the morning of July 1, 2016. Joint
    Prehearing Submission at 4. Next, they dispute whether N.A.’s autopsy slides show
    abnormalities in the hippocampus, specifically granule cell dispersion and/or bilamination of the
    dentate gyrus. 
    Id.
     Additionally, Dr. Miller opines that N.A. had abnormalities in the medulla.
    See Pet. Ex. 22 at 5, 8; Pet. Ex. 65 at 3; Tr. 23, 46-49.
    A.      There Is Not Preponderant Evidence That N.A. Suffered a Seizure
    The undersigned finds that Petitioners did not prove by preponderant evidence that N.A.
    suffered a seizure prior to her death.
    The first reason for this finding is based on N.A.’s individual history. She did not have a
    history of seizures, febrile, or otherwise. None of her medical records identify a history of any
    prior seizures. During periods of prior illness, when N.A. had a fever, she did not experience a
    seizure. Her parents were both health care providers, and they provided detailed histories during
    N.A.’s medical appointments and during the investigation of N.A.’s demise. N.A. had previous
    illnesses, including upper respiratory infections and cellulitis, but during these illnesses, she did
    not experience a febrile seizure. She had also received routine childhood vaccinations prior to
    the vaccination at issue, and she did not have a febrile seizure associated with her vaccinations.
    On the evening prior to her demise, N.A.’s mother noted that she had a low-grade fever and
    Motrin was administered. Her low-grade fever was not elevated to the level that is reportedly
    associated with febrile seizures. See, e.g., Pet. Ex. 16 at 3 (“[Febrile seizures] were defined as a
    seizure associated with illness or fever of ≥ 101°F . . . .”); Resp. Ex. E, Tab 4 at 2 (“The most
    significant risk factor for the development of a first febrile seizure is the height of the
    temperature; the higher the temperature, the higher the likelihood of a febrile seizure. . . . Most
    children have a temperature of at least 39°C at the time of a seizure.”). 84
    In summary, there is no evidence from N.A.’s history to suggest that she ever had a
    seizure, or that illnesses or vaccinations which cause fever ever triggered a seizure.
    N.A. did have a family history of febrile seizures; her brother had several febrile seizures.
    The medical literature shows that this fact may have increased N.A.’s risk to have a febrile
    seizure, but this increased risk does not equate to preponderant evidence. See Tr. 58, 60, 62 (Dr.
    Miller testifying that this is a “rare event”).
    84
    39°C is 102.2°F.
    48
    Next, Dr. Virani, the pathologist who conducted the autopsy, did not opine or suggest that
    a seizure was a contributing factor to the cause of death. Moreover, N.A.’s case was reviewed
    by the SUDCRRC, and they conducted a thorough investigation, including a review of records,
    histology tissue review by a cardiac pathologist and neuropathologist, and genetic analyses.
    They did not conclude that N.A. had a seizure.
    Further, there was no physical evidence to suggest that N.A. had a seizure. As explained
    by Crandell et al., “[p]ostmortem evidence of [a] terminal seizure is often absent or nonspecific.”
    Pet. Ex. 72 at 7. “Common stigma” may include tongue biting or urinary incontinence. 
    Id.
     Due
    to N.A.’s age, urinary incontinence could not be evaluated. But there is no sign or description in
    the autopsy to suggest tongue biting. Thus, there is no physical evidence to support the
    conclusion that that N.A. had a seizure.
    Dr. Virani noted pulmonary edema in his autopsy, but he did not opine that the finding
    suggested or supported febrile seizure as a cause of death. Dr. Kinbsourne mentioned pulmonary
    edema as a finding in support of a seizure, but he did not provide supportive evidence for his
    opinion. Devinsky did not explain why pulmonary edema would occur due to a seizure as
    opposed to another cause of death. And Kloster and Engelskjøn described pulmonary edema as a
    non-specific finding. Moreover, Dr. Miller did not opine that the presence of pulmonary edema
    was significant to him. And none of the pathologists offered opinions about the finding of
    pulmonary edema. The only pathologist with special expertise in pulmonary pathology is Dr.
    Vargas, 85 and she did not see evidence of pulmonary edema in the lung tissue. Resp. Ex. C at 4.
    The undersigned finds that the finding of pulmonary edema on autopsy does not support a
    conclusion that a febrile seizure occurred or caused N.A.’s death.
    Dr. Kinsbourne testified that the body configuration suggested a seizure, but he did not
    explain what about the configuration weighed in favor of finding that a seizure occurred.
    Further, he did not cite any foundational evidence in support of this opinion. Dr. Vargas rejected
    Dr. Kinsbourne’s opinion that there was any unusual posture that suggested a seizure. Her
    opinion on this topic is more persuasive, especially given that Dr. Vargas is a practicing
    pathologist, and Dr. Kinsbourne is long removed from clinical practice and does not have
    expertise in forensic pathology or death investigations. 86
    In conclusion, there is not preponderant evidence that N.A. had a febrile seizure that
    caused or contributed to her death.
    85
    See Resp. Ex. Q at 1-3 (noting a residency in anatomic and clinical pathology, fellowship in
    pediatric pathology, hospital appointments as a pathologist, and Director of Pulmonary
    Pathology at Boston Children’s Hospital); Tr. 161 (noting a pulmonary pathology fellowship and
    a fellowship in pediatric pathology).
    86
    See Pet. Ex. 14 (noting no expertise in forensic pathology); Tr. 90 (noting he is no longer a
    practicing physician since 1981).
    49
    B.      There Is Not Preponderant Evidence of Hippocampal or Medullary
    Abnormality
    At least five neuropathologists and/or forensic pathologists reviewed the brain tissue and
    only Dr. Miller observed any abnormality.
    The pathologist of record, Dr. Virani, took sections of the brain for microscopic analysis
    and did not observe any abnormalities. See Nordwall ex rel. Tori v. Sec’y of Health & Hum.
    Servs., 
    83 Fed. Cl. 477
    , 488 (Fed. Cl. 2008) (“An autopsy report by a medical examiner is
    without question a contemporaneous medical record” that “warrant[s] consideration as
    trustworthy evidence.”). As part of the SUDCRRC case review, the brain tissue was reviewed
    by a neuropathologist. The report states that the neuropathologist reviewed three brain slides and
    found “no significant histopathology.” Pet. Ex. 77 at 8. In addition, forensic pathologist
    reviewers reviewed all 12 autopsy slides. The SUDCRRC study review “was in general
    agreement with the pathologist of record.” 
    Id.
     Thus, the SUDCRRC pathologists agreed with
    Dr. Virani’s assessment that there were no abnormalities of the brain tissue.
    Dr. Miller observed abnormalities of the hippocampus, specifically dysplasia of the
    dentate gyrus and granule cell dispersion and bilamination, and abnormal areas of the medulla,
    lacking in neurons. In response to photomicrographs showing these “abnormalities,” Dr. Lidov
    opined that Dr. Miller magnified images and failed to show the entire field, which had the effect
    of making some tissue appear to show abnormalities. Regardless, Dr. Lidov did not observe any
    abnormalities of the hippocampal or medullary tissue.
    Lastly, Dr. Vargas reviewed the brain tissue and opined there was no pathology.
    Therefore, the undersigned finds that there is not preponderant evidence that N.A. had
    hippocampal or medullary abnormalities or any other brain abnormality.
    VI.    CAUSATION ANALYSIS
    A.      Althen Prong One
    Under Althen prong one, Petitioners must set forth a medical theory explaining how the
    received vaccine could have caused the sustained injury. Andreu, 
    569 F.3d at 1375
    ; Pafford, 451
    F.3d at 1355-56. Petitioners’ theory of causation need not be medically or scientifically certain,
    but it must be informed by a “sound and reliable” medical or scientific explanation. Boatmon,
    941 F.3d at 1359; see also Knudsen, 
    35 F.3d at 548
    ; Veryzer v. Sec’y of Health & Hum. Servs.,
    
    98 Fed. Cl. 214
    , 223 (2011) (noting that special masters are bound by both § 13(b)(1) and
    Vaccine Rule 8(b)(1) to consider only evidence that is both “relevant” and “reliable”). If
    Petitioners rely upon a medical opinion to support their theory, the basis for the opinion and the
    reliability of that basis must be considered in the determination of how much weight to afford the
    offered opinion. See Broekelschen, 618 F.3d at 1347 (“The special master’s decision often times
    is based on the credibility of the experts and the relative persuasiveness of their competing
    theories.”); Perreira v. Sec’y of Health & Hum. Servs., 
    33 F.3d 1375
    , 1377 n.6 (Fed. Cir. 1994)
    50
    (stating that an “expert opinion is no better than the soundness of the reasons supporting it”
    (citing Fehrs v. United States, 
    620 F.2d 255
    , 265 (Ct. Cl. 1980))).
    The undersigned acknowledges that the parties have stipulated that the MMRV vaccine
    can cause febrile seizures. For the following reasons, however, the undersigned finds Petitioners
    have failed to provide preponderant evidence of a sound and reliable theory to explain how the
    MMRV vaccine can cause a seizure in a vulnerable child which can lead to death.
    Petitioners’ experts have opined that the MMRV vaccine caused a febrile seizure in the
    context of hippocampal and medullary brain abnormalities, rendering the child vulnerable to
    sudden unexplained death. As such, Petitioners’ theory of causation relies on two factual
    presumptions: (1) that a febrile seizure occurred before death and (2) that there were brain
    abnormalities that increased the risk of sudden death. Because there is not preponderant
    evidence of these facts, Petitioners’ causal theory fails. Even if there was factual support for
    Petitioners’ theory, there are additional reasons why the undersigned finds that Petitioners have
    failed to provide evidence of a sound and reliable theory by preponderant evidence. 87
    First, the language used by both Dr. Miller and Dr. Kinsbourne to express their opinions
    suggests they hold their opinions to a lower threshold than the preponderant standard required by
    the Vaccine Act. Dr. Miller uses the phrase “medically plausible.” See Pet. Ex. 22 at 9
    (“[T]here is a scientifically and medically plausible means to connect these events.”); Pet. Ex. 22
    at 13 (“This chain of events represents a highly plausible, scientifically valid, hypothesis.”).
    “Medical plausibility,” however, is insufficient to reach the standard required. See, e.g.,
    Boatmon, 941 F.3d at 1359-60 (citing Federal Circuit case law “reiterat[ing] that a ‘plausible’ or
    ‘possible’ causal theory does not satisfy the standard”); Moberly, 
    592 F.3d at 1322
     (finding
    Petitioners’ characterization that the vaccine “likely caused” the injury to appear “closer to proof
    of a ‘plausible’ or ‘possible’ causal link between the vaccine and the injury, which is not the
    statutory standard”); LaLonde v. Sec’y of Health & Hum. Servs., 
    746 F.3d 1334
    , 1339 (Fed. Cir.
    2014) (“[W]e have made clear that simply identifying a ‘plausible’ theory of causation is
    insufficient for a petitioner to meet her burden of proof.”).
    In Boatmon, the Federal Circuit found that Dr. Miller 88 presented a theory that was “only
    ‘plausible.’” Boatmon, 941 F.3d at 1360. The Circuit found that the characterization of the
    standard of proof as “plausible” was “incorrect as a matter of law.” Id. Application of the
    holding in Boatmon renders Dr. Miller’s opinions insufficient here. Thus, the undersigned finds
    that Dr. Miller did not prove by preponderant evidence a sound and reliable causal theory to
    satisfy Althen prong one.
    87
    In other words, the undersigned’s rulings as to the factual predicates proposed by Petitioners
    are not determinative as to Althen prong one. There are independent reasons that the
    undersigned finds Petitioners have failed to prove Althen prong one as explained herein.
    88
    Dr. Miller is the same expert who testified on behalf of the Petitioners in Boatmon. See
    Boatmon, 
    941 F.3d 1351
    .
    51
    Dr. Kinsbourne also used words that reflect a lower burden of proof. For example, he
    testified that unobserved seizures “undoubtedly” occur and can cause death. Tr. 84-85; see also
    Pet. Ex. 61 at 3 (“The rarity of death . . . does not suggest that unwitnessed febrile seizures don’t
    cause death.”). Both experts couched their opinions in terms of “significant,” “elevated,” or
    “increased risk.” They stated there was an “increased risk” of febrile seizure. Pet. Ex. 22 at 8;
    Pet. Ex. 61 at 2. They also cited medical literature that used the same phrase or similar phrases.
    See, e.g., Pet. Ex. 16 at 1 (“[T]erminal fever may increase the risk for an unwitnessed terminal
    seizure”); Pet. Ex. 72 at 7 (“We speculate that [febrile seizures] occur in some children without a
    known [febrile seizures] history . . . .”). An increased risk, however, is not the same as
    preponderant evidence of seizures. See, e.g., Pet. Ex. 21 at 6 (explaining “potential benefits must
    be balanced by the increased risk (albeit small) of febrile seizures”); Resp. Ex. E, Tab 1 at 2
    (discussing “the rarity of death during febrile convulsions”); Resp. Ex. U at 3 (“The mortality
    associated with febrile seizures is extremely low.”); Resp. Ex. L at 2 (noting “the absolute risk of
    death [from febrile seizure] [is] [] very low”). As the medical literature aptly establishes, an
    increased risk of having a seizure, when the likelihood is still very low, does not rise to the level
    of preponderant evidence.
    Next, the part of Petitioners’ causal theory based on pathological abnormalities is
    controversial, particularly the hypothesis advanced by Dr. Kinney and her colleagues related to
    hippocampal abnormalities. Literature filed by Respondent’s experts suggest that the
    hippocampal abnormalities described by Kinney et al. are not pathological but may be “normal
    variants” and not unique to children who have seizures or epilepsy. See, e.g., Resp. Ex. I, Tab 1
    at 18. In 2020, Roy et al. studied pediatric hippocampal tissue from 147 autopsies and found that
    “granule cell dispersion is within the spectrum of normal variation.” 
    Id. at 1
    . Another smaller
    study, also published in 2020, from a group at Yale reported “[their] failure to identify a
    significant relationship between the frequency or type of hippocampal lesions among patients
    with and without a history of seizure, or with lifetime seizure frequency, suggests that
    pathophysiological conclusions should remain tentative.” Resp. Ex. J, Tab 5 at 8. And in 2021,
    Leitner et al. conducted a blind review of hippocampal tissues in sudden death cases, and
    reported a “lack of an association of hippocampal findings in SUDC and controls, as well as
    inconsistency of observations by multiple blinded reviewers, indicat[ing] discrepancy with
    previous studies.” Resp. Ex. K at 2.
    In short, current studies question the significance of hippocampal abnormalities and the
    relationship between such abnormalities and seizures and/or sudden death. There is no
    consensus on these issues and more research is recommended. Thus, the undersigned finds that
    Petitioners’ reliance on hippocampal abnormalities as part of their theory is not sound or reliable.
    The undersigned also finds that Petitioners’ reliance on the idea that hippocampal abnormalities
    cause children to be vulnerable and at risk of sudden death is likewise not sound or reliable. 89
    Further, the Petitioners’ theory is not sound and reliable because they have extrapolated
    information taken from studies that relate to children with epilepsy (SUDEP) and applied it to
    89
    Whether N.A. had or did not have hippocampal abnormalities is not determinative of the
    undersigned’s finding as to Althen prong one. There are other independent reasons for the
    undersigned’s determination as described herein.
    52
    children who do not have epilepsy or a history of prior seizures. The studies cited note
    comparisons between SUDC and SUDEP, and question whether the pathophysiology which
    leads to fatal seizures in children with epilepsy may be relevant to unexplained deaths of
    children, but they do not reach any conclusions that are transferable to the facts and
    circumstances here.
    Dr. Miller testified that the mechanism in SUDC is “similar or identical” to the
    hypothesis described in SUDEP. Tr. 68. Several articles cited by the experts discuss this
    subject. For example, Kon et al. noted that hippocampal abnormalities are associated with
    epilepsy and are thought to predispose individuals to seizures. But this hypothesis is not well
    studied and more research is needed, as explained in the case report by Dlouhy et al.
    Moreover, there is not preponderant evidence that febrile seizures alone in a child without
    epilepsy can lead to seizure-induced death. Dlouhy et al. noted that febrile seizures are thought
    to be benign, and they stated that “no reported cases of febrile seizure-induced death have been
    documented.” Pet. Ex. 70 at 2. The authors propose that the same pathophysiological
    mechanism that occurs in SUDEP could explain some cases of SUDC. 
    Id. at 4
    . The process
    thought to occur in SUDEP starts with a generalized tonic-clonic seizure, which leads to
    “respiratory dysfunction and hypoxemia,” and it is “exacerbated by [the child] being facedown in
    bed, during sleep, and which ultimately leads to bradycardia and asystole.” 
    Id. at 3
    . The
    disconnect is that children with epilepsy may have genetic mutations or brain abnormalities
    distinct from other children. Dlouhy et al. describes some of these mutations (Dravet syndrome,
    temporal lobe epilepsy, and other genetic abnormalities that encode ion channels). 
    Id. at 4
    .
    However, it is premature to conclude that the mechanism at play in children with epilepsy could
    explain deaths in children without epilepsy. As the authors in Dlouhy et al. state, “[f]urther
    study is needed.” 
    Id.
     They also state that “further evidence may support that . . . some cases of
    sudden death are induced by provoked seizures,” but they do not conclude that the current
    evidence supports such a finding. Id.; see also Resp. Ex. L at 1-2 (finding “the hypothesis that
    febrile seizures are associated with an increased risk of death” to not be supported by large study
    in Denmark where the “increased risk of death after febrile seizure was seen only in children
    with complex febrile seizures and in those with underlying neurological abnormalities”); Pet. Ex.
    74 at 3 tbl.1, 8-9 (showing genetic associations in febrile seizures, SUDC, and SUDEP).
    In summary, Petitioners have failed to offer preponderant evidence of a sound and
    reliable medical theory in support of their claim. Thus, the undersigned finds Petitioners have
    failed to provide preponderant evidence with respect to the first Althen prong.
    B.      Althen Prong Two
    Under Althen prong two, Petitioners must prove by a preponderance of the evidence that
    there is a “logical sequence of cause and effect showing that the vaccination was the reason for
    the injury.” Capizzano, 
    440 F.3d at 1324
     (quoting Althen, 
    418 F.3d at 1278
    ). “Petitioner[s]
    must show that the vaccine was the ‘but for’ cause of the harm . . . or in other words, that the
    vaccine was the ‘reason for the injury.’” Pafford, 451 F.3d at 1356 (internal citations omitted).
    53
    In evaluating whether this prong is satisfied, the opinions and views of the vaccinee’s
    treating physicians are entitled to some weight. Andreu, 
    569 F.3d at 1367
    ; Capizzano, 
    440 F.3d at 1326
     (“[M]edical records and medical opinion testimony are favored in vaccine cases, as
    treating physicians are likely to be in the best position to determine whether a ‘logical sequence
    of cause and effect show[s] that the vaccination was the reason for the injury.’” (quoting Althen,
    
    418 F.3d at 1280
    )). Medical records are generally viewed as trustworthy evidence, since they are
    created contemporaneously with the treatment of the vaccinee. Cucuras, 
    993 F.2d at 1528
    .
    Petitioners need not make a specific type of evidentiary showing, i.e., “epidemiologic studies,
    rechallenge, the presence of pathological markers or genetic predisposition, or general
    acceptance in the scientific or medical communities to establish a logical sequence of cause and
    effect.” Capizzano, 
    440 F.3d at 1325
    . Instead, Petitioners may satisfy their burden by presenting
    circumstantial evidence and reliable medical opinions. 
    Id. at 1325-26
    .
    Since Petitioners failed to prove the factual predicates underlying their theory, and failed
    to prove Althen prong one, it follows that they cannot prove Althen prong two. To summarize,
    Petitioners’ experts opined that the MMRV vaccination administered to N.A. on June 23, lead to
    a fever on June 30, that provoked a seizure that night, which caused N.A.’s death. Since the
    undersigned finds that Petitioners’ have failed to establish preponderant evidence that N.A. had a
    seizure, there is no logical sequence of cause and effect. Similarly, Petitioners’ experts opined
    that N.A. had an underlying vulnerability due to her brain abnormalities. As the undersigned
    finds that Petitioners did not prove N.A. had brain abnormalities by preponderant evidence, the
    undersigned also finds that she did not have a vulnerability which put her at risk for a seizure.
    As Petitioners have not proven this aspect of their theory by preponderant evidence, the
    undersigned finds that they have failed to show by preponderant evidence a logical sequence of
    cause and effect.
    Further, none of N.A.’s treating physicians or pathologists who conducted the autopsy or
    the SUDCRRC case review attributed N.A.’s death to either a seizure or her vaccinations. Dr.
    Virani opined that the cause of death was asphyxia. There is no suggestion in his report that he
    causally associated her death to a seizure or her MMRV vaccination. Several pathologists
    participated in the SUDCRRC case review, including a cardiologist, neuropathologist, and
    forensic pathologist. They concluded that N.A.’s cause of death was “[u]nexplained sudden
    death” and the manner of death was “[u]ndetermined.” Pet. Ex. 77 at 9. While they noted the
    fact that N.A. had received her MMRV vaccination, they did not attribute her death to a seizure
    or to her vaccination. See Capizzano, 
    440 F.3d at 1326
     (noting “treating physicians are likely to
    be in the best position to determine whether a ‘logical sequence of cause and effect show[s] that
    the vaccination was the reason for the injury.’” (quoting Althen, 
    418 F.3d at 1280
    )); Cucuras,
    
    993 F.2d at 1528
     (explaining medical records are generally more reliable because they are
    created contemporaneously with the treatment of the vaccinee).
    Regarding the brain abnormalities, Dr. Miller conceded that dentate gyrus dysplasia is a
    very common finding in all ages and all types of deaths. This observation suggests that dysplasia
    is a non-specific finding, not unique to SUDC, and not supportive of Petitioners’ theory that
    N.A. had a vulnerability due to her abnormal brain tissue.
    54
    Next, the undersigned finds that Petitioners’ experts offered opinions about underlying
    presumptions based on statistics. For example, Dr. Miller’s opinion that N.A.’s fever was based
    on her vaccination and not on her viral infection was based on statistics. He was asked to discuss
    the cause of N.A.’s fever in light of the fact that her sister was diagnosed with a viral infection
    the day after N.A.’s death. Specifically, Dr. Miller was asked how he could be certain N.A.’s
    fever was from the vaccine instead of a potential virus. Dr. Miller responded that he based his
    answer on
    [s]tatistics. . . . [C]hildren get colds, and they don’t generally die of them. They
    don’t generally have fever with colds. There is a described increased risk for both
    fever and febrile seizures in children who got the MMRV vaccine compared to
    children who got all other vaccines, including the MMR without the V. It’s a
    significantly increased risk. It’s still a very rare event, but it’s a definite increased
    incidence.
    Tr. 60.
    Similarly, Dr. Kinsbourne testified that a child is “seven times more likely” to have a
    seizure after MMRV vaccination. Tr. 79. He was unable, however, to reference the citation for
    this statistic. Regardless, he was using statistical data to support his opinion that N.A. had a
    seizure after vaccination.
    It would be error for the undersigned to accept Dr. Miller’s and Dr. Kinsbourne’s
    opinions about what happened to N.A. based on statistics. In Boatmon, the Circuit found “the
    Special Master’s determination that [the child] had a brainstem abnormality rested in part on an
    assumption based on statistics.” Boatmon, 941 F.3d at 1362-63. And this is insufficient proof of
    causation. See id. at 1363 (explaining the Circuit has “previously rejected statistical likelihood
    alone as proof of actual causation”); see also Knudsen, 
    35 F.3d at 550
     (rejecting a theory based
    on a “bare statistical fact”).
    For these reasons, as well as the reasons described above as they relate to the factual
    findings specific to N.A., the undersigned finds Petitioners have failed to show by preponderant
    evidence that there is a logical sequence of cause and effect showing N.A.’s MMRV vaccine
    caused a fatal seizure or otherwise caused her death.
    Accordingly, the undersigned finds that Petitioners have failed to provide preponderant
    evidence of a logical sequence of cause and effect to satisfy their burden under Althen prong
    two.
    C.      Althen Prong Three
    Althen prong three requires Petitioners to establish a “proximate temporal relationship”
    between the vaccination and the injury alleged. Althen, 
    418 F.3d at 1281
    . That term has been
    defined as a “medically acceptable temporal relationship.” 
    Id.
     Petitioners must offer
    “preponderant proof that the onset of symptoms occurred within a time frame for which, given
    the medical understanding of the disorder’s etiology, it is medically acceptable to infer
    55
    causation-in-fact.” de Bazan, 
    539 F.3d at 1352
    . The explanation for what is a medically
    acceptable time frame must also coincide with the theory of how the relevant vaccine can cause
    the injury alleged (under Althen prong one). Id.; Koehn v. Sec’y of Health & Hum. Servs., 
    773 F.3d 1239
    , 1243 (Fed. Cir. 2014); Shapiro, 
    101 Fed. Cl. at 542
    ; see also Pafford, 451 F.3d at
    1358. A temporal relationship between a vaccine and an injury, standing alone, does not
    constitute preponderant evidence of vaccine causation. See, e.g., Veryzer, 100 Fed. Cl. at 356
    (explaining that “a temporal relationship alone will not demonstrate the requisite causal link and
    that [P]etitioner must posit a medical theory causally connecting the vaccine and injury”).
    The parties stipulate that there is a temporal association here. Joint Prehearing
    Submission at 4 (“Most [MMRV] vaccine related seizures occur [seven] to 10 days after a child
    has received the MMRV vaccine.”). Dr. Miller and Dr. Kinsbourne both opined that the MMRV
    vaccine can lead to fevers and seizure seven to 10 days after vaccination. Respondent’s experts
    did not disagree. Therefore, the undersigned finds that Petitioners have provided preponderant
    evidence satisfying Althen prong three. However, a temporal association, without more, is
    insufficient. Moberly, 
    592 F.3d at 1323
    ; Grant, 956 F.2d at 1148 (“[A] proximate temporal
    association alone does not suffice to show a causal link between the vaccination and the
    injury.”). Therefore, Petitioners are not entitled to compensation.
    VII.   CONCLUSION
    This is a heartbreaking case. The undersigned extends her sympathy to Petitioners for
    their terrible loss. The undersigned’s Decision, however, cannot be decided based upon
    sympathy, but rather on the evidence and law.
    For the reasons discussed above, the undersigned finds that Petitioners have failed to
    establish by preponderant evidence that N.A.’s MMRV vaccination caused her death. Therefore,
    Petitioners are not entitled to compensation and the petition must be dismissed.
    In the absence of a timely filed motion for review pursuant to Vaccine Rule 23, the Clerk
    of Court SHALL ENTER JUDGMENT in accordance with this Decision.
    IT IS SO ORDERED.
    s/Nora Beth Dorsey
    Nora Beth Dorsey
    Special Master
    56
    

Document Info

Docket Number: 17-2061V

Judges: Nora Beth Dorsey

Filed Date: 12/26/2023

Precedential Status: Non-Precedential

Modified Date: 11/8/2024