Hayward v. Secretary of Health and Human Services ( 2018 )


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  •                In the United States Court of Federal Claims
    OFFICE OF SPECIAL MASTERS
    No. 15-005V
    (not to be published)
    *************************                                                 Special Master Corcoran
    *
    MARION EUGENE HAYWARD,     *
    *
    Petitioner, *                                              Filed: May 4, 2018
    *
    v.               *                                              Motion to Dismiss; Ruling on the
    *                                              Record; Decision without Hearing;
    SECRETARY OF HEALTH        *                                              Influenza (“Flu”) Vaccine; Left
    AND HUMAN SERVICES,        *                                              Brain Cerebrovascular Accident
    *                                              (“CVA”); Thromboembolic
    Respondent. *                                              Condition; Significant Aggravation.
    *
    *************************
    Howard Gold, Gold Law Firm, LLC, Wellesley Hills, MA, for Petitioner.
    Sarah C. Duncan, U.S. Dep’t of Justice, Washington, DC, for Respondent.
    DECISION DISMISSING PETITION1
    On January 5, 2015, Marion Eugene Hayward filed a petition seeking compensation under
    the National Vaccine Injury Compensation Program (“Vaccine Program”).2 In it, Mr. Hayward
    alleged that the influenza (“flu”) vaccine he received on January 7, 2012, caused him either to
    experience a left brain cerebrovascular accident (“CVA”), plus stroke and a thromboembolic
    condition that same day, or that those conditions were significantly aggravated by the flu vaccine.
    Petition at 1, Mot. at 1.
    1
    Although this Decision has been formally designated “not to be published,” it will nevertheless be posted on the
    Court of Federal Claims’s website in accordance with the E-Government Act of 2002, 
    44 U.S.C. § 3501
     (2012)). This
    means that the Decision will be available to anyone with access to the internet. As provided by 42 U.S.C. § 300aa-
    12(d)(4)(B), however, the parties may object to the Decision’s inclusion of certain kinds of confidential information.
    Specifically, under Vaccine Rule 18(b), each party has fourteen days within which to request redaction “of any
    information furnished by that party: (1) that is a trade secret or commercial or financial in substance and is privileged
    or confidential; or (2) that includes medical files or similar files, the disclosure of which would constitute a clearly
    unwarranted invasion of privacy.” Vaccine Rule 18(b). Otherwise, the whole Decision will be available to the public.
    Id.
    2
    The Vaccine Program comprises Part 2 of the National Childhood Vaccine Injury Act of 1986, Pub. L. No. 99-660,
    
    100 Stat. 3758
    , codified as amended, 42 U.S.C. §§ 300aa-10 through 34 (2012) [hereinafter “Vaccine Act” or “the
    Act”]. Individual section references hereafter will be to § 300aa of the Act.
    After the parties filed expert reports, and based upon my initial review of the case record
    and familiarity with central features of Petitioner’s causation theory, I proposed (and the parties
    agreed) that the matter be decided without holding an evidentiary hearing, and I established a
    schedule for briefing the substantive merits of Petitioner’s claim. To that end, Petitioner filed a
    motion in support of his claim, dated September 5, 2017 (ECF No. 34) (“Mot.”), and Respondent
    requested dismissal of the claim by brief dated November 3, 2017 (ECF No. 36) (“Opp.”).
    Having completed my review of the evidentiary record and the parties’ filings, I hereby
    DENY Petitioner’s request for compensation, and dismiss the claim. The record strongly
    establishes that Petitioner had already experienced a thromboembolic condition and/or CVA
    before his vaccination. Petitioner has not otherwise established that the vaccine significantly
    aggravated his condition, nor has he persuasively established that the vaccine could do so in
    accordance with the components of his causation theory, and in so short a timeframe.
    I.          FACTUAL BACKGROUND
    Vaccination and Alleged Immediate Reaction
    Mr. Hayward received the flu vaccine on January 7, 2012, when he was 74 years old. Ex.
    3 at 1. The vaccination record does not indicate the time of the vaccine’s administration, but in an
    affidavit submitted in this case Petitioner averred that he received it at approximately 9:00 a.m.
    Ex. 10 at ¶ 2. Petitioner’s pre-vaccination medical history was significant for benign prostatic
    hypertrophy,3 pyelonephritis,4 and childhood poliomyelitis. Ex. 4 at 1, 6. The records do not
    include any allegation of a reaction to the vaccine, and Petitioner has not asserted otherwise.
    In the evening of that same day, Mr. Hayward went to the Emergency Room at Eaton
    Rapids Medical Center in Eaton Rapids, Michigan, complaining of sudden onset right-sided
    weakness starting around 7:00 p.m., during his dinner. Ex. 6 at 1-12. Petitioner specifically
    informed treaters that his right arm had become numb, and that the numbness had then spread to
    his leg. Id. at 5. He stated “I think I’m having a stroke,” but did not inform treaters of having
    experienced a reaction to the vaccine earlier that day. Id. at 2. He was noted to have facial droop,
    weakness, tingling, impaired speech, and poor coordination. Id. Petitioner’s bloodwork showed
    normal hematology counts, high glucose, and normal cardiac enzymes. Id. at 4. A head CT scan
    performed around 8:00 p.m. revealed a “somewhat wedge shaped area of edema within the right
    temporal occipital region,” “lacunar infarct in the posterior left thalamus, likely chronic,” and
    “mild diffuse cortical atrophy.” Id. at 13 (emphasis added). A chest x-ray and EKG were
    unremarkable. Id. at 14-16. Based upon all of the above, Petitioner’s initial treaters proposed he
    3
    Benign prostatic hypertrophy is a condition involving enlargement of the prostate due to proliferation of both
    glandular and stromal elements, and is known to begin with males at age 50. Dorland’s Illustrated Medical Dictionary
    at 894 (32nd ed. 2012) (hereinafter Dorland’s).
    4
    Pyelonephritis is inflammation of the kidney and renal pelvis due to a bacterial infection. Dorland’s at 1559.
    2
    was experiencing a CVA or stroke, with cerebral artery thrombosis but without cerebral
    infarction.5 Id. at 1.
    Mr. Hayward was immediately transferred to Sparrow Hospital in Lansing, Michigan,
    where he was hospitalized for several days. Ex. 6 at 1, Ex. 7 at 384-85. Testing performed on
    Petitioner at this time provided additional details relevant to the symptoms that had resulted in his
    ER visit. Thus, a brain MRI performed at about 7:30 a.m. the following morning (January 8, 2012)
    revealed “right parietal and left thalamic stroke or infarct.” Id. at 384. The radiologist performing
    the MRI noted “some mild blood product formation . . . as well as some minimal focal edema and
    enhancement following contrast administration. Primary consideration is given to a subacute
    infarct . . . . Given the bilaterally of lesions, an embolic phenomenon is a consideration . . .” Ex. 5
    at 4-5 (emphasis added). In addition, a CT angiogram of the neck and brain performed the same
    day observed a “[r]ight saddle pulmonary embolism6 with involvement of the right upper, middle,
    and lower lobes.” Id. at 6-7; Ex. 7 at 452. A venous Doppler examination of both sides of his lower
    extremities, by contrast, did not show any evidence of deep vein thrombosis (“DVT”). Ex. 5 at 8.
    A CT of the thorax, abdomen, and pelvis on January 9, 2012, showed a pulmonary embolism in
    the right lung and coronary artery calcification. Id. at 10-12. And an echocardiogram performed
    the same day revealed diastolic dysfunction and a sclerotic aortic valve. Ex. 4 at 3.
    On January 12, 2012, Petitioner was transferred to inpatient rehabilitation at Sparrow
    Health System, where he remained until January 25, 2012. Ex. 4 at 6-11. Petitioner was noted to
    be in a hypercoagulable state with cerebrovascular occlusions and a pulmonary embolus. Id. at 8-
    9. Petitioner gradually improved, however, with his pulmonary embolism resolving by January 23,
    2012. Id. By his discharge, he was able to walk 400 feet and move from sitting to standing
    independently, jog 300 feet with standby assistance, climb up and down one flight of stairs with
    rail-modified independence, and complete a mental test with moderate verbal cues. Id.
    Post-Hospitalization History
    Petitioner was thereafter discharged home with a Coumadin7 prescription. Ex. 4 at 8. He
    was deemed to be in stable condition and given a recommendation for outpatient occupational and
    physical therapy (“OT” and “PT”), along with instructions to follow up with his primary care
    physician and neurologist. Id. Between January 31 and April 11, 2012, Petitioner attended PT. Id.
    at 37. He reported overall improvement, with minimal loss of balance periodically, plus
    5
    A cerebral infarction is “an ischemic condition of the brain, producing local tissue death and usually a persistent
    focal neurological deficit in the area of distribution of one of the cerebral arteries.” Dorland’s at 934.
    6
    A saddle pulmonary embolism (PE) is a form of large pulmonary thromboembolism (blood clot causing blood vessel
    obstruction) that straddles the main pulmonary arterial trunk at its bifurcation. Dorland’s at 606.
    7
    Coumadin is the trademarked name for warfarin sodium, which is an anticoagulant used for the treatment and
    prophylaxis of thromboembolic disorder. Dorland’s at 2074-75.
    3
    improvement in the “buzzing” sensation he had previously experienced in his right lower
    extremity. Id. He was also able to return to normal activities, though his “foot still fe[lt] like a
    block.” Id.
    Mr. Hayward saw his primary care physician, Peter Luea, M.D., three times in February
    2012, for follow up. See generally Ex. 4 at 16-18, 20-23, 25-28. He informed Dr. Luea that he was
    experiencing about a twenty percent improvement in his right foot, thigh, and arm sensations. Id.
    at 16-18. He also saw a neurologist, Dr. Anmar Razak, on February 22, 2012. Ex. 5 at 19-22.
    Petitioner’s hypercoagulable work-up was negative, and his neurologic exam was essentially
    normal. Id. Dr. Razak’s assessment was “residual of mild right[-]sided paresthesias,” and
    recommended another brain MRI in a month and a transesophageal echocardiogram (“TEE”) to
    rule out patent foramen ovale.8 Id.
    On March 22, 2012, Mr. Hayward underwent the brain MRI Dr. Razak had recommended.
    Ex. 4 at 36. The ischemic infarcts previously identified in his January MRI were now seen to be
    in a “subacute-to-chronic state.” Id. There were also a few small punctate T2 hyper-intensities in
    the white matter, and they were deemed age-related chronic ischemic changes. Id. At a follow-up
    visit in April, Dr. Razak noted that the MRI had confirmed the evolution of Petitioner’s previous
    strokes with no new events, and that a TEE performed on him had been negative for heart disease.
    Ex. 5 at 23-26. Dr. Razak recommended that Petitioner continue taking Coumadin until August
    2012 (before switching to an aspirin regimen) and encouraged Petitioner to maintain a healthy
    weight through exercise and diet. Id. at 26.
    Petitioner followed up with Dr. Luea every month for the rest of 2012. See generally Ex. 4
    at 38-41, 43-45, 47-51, 59-62, 65-68, 70-73, 82-84, and 89-92. Throughout this time, Mr.
    Hayward’s health was described as “fair,” although he variously reported difficulty walking, limb
    weakness, tingling, leg swelling, myalgias, nocturia, decreased sensation in the right cheek, right
    ankle joint pain, and benign prostatic hypertrophy. By August 2012, Petitioner reported itching
    and the return of sensation on his right side, and Dr. Luea instructed him to stop taking Coumadin
    and start instead on low dose aspirin. Id. at 70-73. He also saw Dr. Razak in September, informing
    him that he was still experiencing some continued right-sided paresthesias and problems walking
    because his right ankle and foot tingled. Pet. Ex. 5 at 29-32. To help with those symptoms, Dr.
    Razak prescribed Neurontin. Id. at 32.
    Importantly, there is no evidence from any of Mr. Hayward’s 2012 medical records
    revealing an instance in which any treater ever proposed or opined that the flu vaccine had anything
    to do with his subsequent medical conditions or problems.
    8
    Patent foramen ovale, or PFO, is a type of heart septal defect consisting of abnormal persistence of the fetal foramen
    ovale cordis after birth, often resulting in a left-to-right or right-to-left shunt. Dorland’s at 730.
    4
    Repeat Hospitalization in 2013
    After a long period of relative quiescence, Mr. Hayward experienced another acute event
    requiring immediate intervention. On July 28, 2013 (now about eighteen months since Petitioner
    received the flu vaccine), he was admitted to Eaton Rapids Medical Center with a two-day history
    of right chest pain that had progressively worsened. Ex. 4 at 127-28. A chest CT showed a large
    embolus in the right pulmonary arterial tree, with an area suspicious for pulmonary infarction in
    the right lower lobe. Id. at 124. A head CT did not reveal any acute abnormality, however. Id. at
    123. Petitioner was noted to have a longstanding history of CVA, a family history of a clotting
    disorder, and a history of pulmonary embolism. Id. at 127-28. A venous Doppler examination on
    July 29, 2013, revealed no evidence of DVT. Id. at 129. He was discharged on August 1, 2013,
    and again prescribed Coumadin. Id. at 130-31. At an August 8, 2013, follow-up visit with Dr.
    Luea, Mr. Hayward reported fatigue and some shortness of breath, plus chronic right-sided
    “woodiness,” but no chest pain. Id. at 134-36.
    On September 11, 2013, Mr. Hayward had an appointment with a hematologist. Ex. 4 at
    157-59. In providing a medical history background, Petitioner related the following to a
    physician’s assistant:
    [T]here was some concern that he had an influenza vaccine the day of his stroke and this
    was with a company who had used mercury for preservation and that there had actually
    been several other incidences where someone who had gotten that influenza vaccine with
    mercury had developed strokes so there is concern that the stroke this patient had may have
    been caused by the mercury.
    Id. Neither the hematologist nor the physician’s assistant commented on this statement, but the
    medical records also noted that “[t]here is an unknown reason why this patient has had recurrent
    pulmonary embolisms at this time.” Id. This record does not detail which prior providers might
    have expressed to or shared with Petitioner any concern about the flu vaccine’s purported role in
    his strokes or other injuries.
    Besides the above, Petitioner filed other medical records pertaining to his subsequent
    treatment with Dr. Luea from the remainder of 2013 through August 2015, but these records do
    not bear on resolution of the issues in dispute, and therefore are not discussed herein. See generally
    Ex. 4 at 162-64, 168-70, 174-77, 184-86, 190-93, 196-99, 202-05, 208-11, 219-22, 229-32, 235-
    38, 242-45, 249-54, 264-68, 274-78, 281-85, 288-91, 295-98, 307-10; Pet. Ex. 8. No records
    detailing subsequent treatment were filed.
    5
    II.     EXPERT REPORTS
    A.       Dr. David Axelrod
    Petitioner submitted a single expert report from Dr. Axelrod, a clinical immunologist. See
    Report, dated March 24, 2016, filed as Ex. 9-A (ECF No. 21-1) (“Axelrod Rep.”).
    Dr. Axelrod graduated from the University of Michigan Medical School in 1974 (after
    obtaining his bachelor’s degree at Michigan as well). Ex 19-B (ECF No. 21-2) (“Axelrod CV”) at
    1. He completed two residencies in internal medicine, one at the University of Toronto and one at
    William Beaumont Hospital, followed by additional residencies with a fellowship in allergy,
    immunology, and rheumatology at McGill University. Axelrod CV at 1. He then served as a fellow
    for the National Institutes of Health in the Clinical Immunology Laboratory. Id. Dr. Axelrod is
    board certified in medicine, allergy and immunology, adult rheumatology, and medical laboratory
    immunology. Id. He currently works in private practice, with the vast majority of his patients
    having allergies, immunologic conditions, or autoimmune rheumatic diseases. Id. He does not
    appear, however, to have conducted research in immunologic matters that bear on stroke or CVA
    causality, nor has he demonstrated expertise with respect to those specific conditions.
    Dr. Axelrod proposes that immunologic processes initiated by receipt of the flu vaccine
    “caused or contributed to the acute infarction . . . and pulmonary emboli” Petitioner experienced.
    Axelrod Rep. at 3. First, he opined that the vaccines at issue could cause the production of certain
    proinflammatory cytokines9 immediately upon administration. Axelrod Rep. at 2. As shown by Y.
    Kashiwagi, et al., Production of Inflammatory Cytokines in Response to Diphtheria-Pertussis-
    Tetanus (DPT), Haemophilus Influenzae Type B (Hib), and 7-Valent Pneumococcal (PCV7)
    Vaccines, 10 Human Vaccines & Immunotherapeutics 3:677-85 (2014), filed as Ex. 19-C (ECF
    No. 21-3) (“Kashiwagi”), vaccination results in elevated levels of four kinds of cytokines. Id. at 1;
    Kashiwagi at 678. Kashiwagi was an in vitro study comparing the levels of inflammatory cytokines
    in the blood sera of 61 vaccine recipients with febrile illness, against 18 recipients without febrile
    illness, 24 hours after vaccination. Id. at 677. The study’s authors began with peripheral blood
    mononuclear cell cultures and then introduced different combinations (separately or concurrently)
    of the DTaP, Hib, and/or PCV7 vaccines in order to determine the levels of cytokine production
    in the cell cultures. Id.
    Relying on Kashiwagi, Dr. Axelrod maintained that certain proinflammatory cytokines are
    produced beginning six hours after vaccination, and then continue to increase up to 24 hours
    following vaccination. Axelrod Rep. at 1. He also maintained that these elevated levels were found
    to persist beyond a 24-hour timeframe. Id.; see also B. Ferko, et al., Immunogenicity and
    Protection Efficacy of Replication-deficient Influenza A Viruses with Altered NS1 Genes, 78 J
    Virology 13037 (2004), filed as Ex. 19-D (ECF No. 21-4).
    9
    A cytokine is a generic term for non-antibody proteins released by one cell population on contact with a specific
    antigen, which act as intercellular mediators in connection with an immune response. Dorland’s at 466. The term
    “proinflammatory” signifies that these cytokines are capable of stimulating inflammation. Id. at 1523.
    6
    Yet there are reasons to distinguish Kashiwagi and articles like it from the present matter,
    and to find that its conclusions, however reliable, are less compelling than Dr. Axelrod proposes.
    The results showing increased cytokine production were mainly seen in connection with the PCV7
    vaccine, which is not the relevant vaccine in this case. Kashiwagi at 679. More significantly,
    Kashiwagi found no real difference between the two compared serum groups, beyond the fact that
    one particular type of cytokine was elevated in individuals already experiencing a febrile illness.
    Id. at 680. Because Kashiwagi’s authors admitted that “[v]accine-specific innate inflammatory
    responses . . . have not been sufficiently investigated regarding cytokine production using
    difference vaccines,” they could not characterize this instance of cytokine elevation as significant
    (id. at 678), and ultimately concluded that more analysis was required. Id. at 683.
    Besides asserting that the flu vaccine can cause the fast upregulation of cytokines, Dr.
    Axelrod’s theory proposed that this increase in cytokines could in turn “cause blood clots within
    the blood vessels.” Axelrod Rep. at 3. He cited several pieces of medical literature to support this
    point. See, e.g., P. Bunce, Pandemic H1N1 Influenza Infection and Vascular Thrombosis, 52
    Clinical Infectious Diseases e14-17 (2011), filed as Ex. 9-G (ECF No. 21-7)(“Bunce”); S.
    Wiseman, et al., Blood Markers of Coagulation, Fibrinolysis, Endothelial Dysfunction and
    Inflammation in Lacunar Stroke Versus Non-Lacunar Stroke and Non-Stroke: Systematic Review
    and Meta-analysis, 37 Cerebrovascular Disease 64 (2014), filed as Ex. 9-H (ECF No. 21-8)
    (“Wiseman”); H. Kimura, et al., Interleukin-1 Beta (IL-1 beta) Induces Thrombocytosis in Mice:
    Possible Implication of IL-6, 76 Blood 2493 (1990), filed as Ex. 9-J (ECF No. 21-10) (“Kimura”).
    The first of the articles, Bunce, observed 119 patients who had been infected with the 2009
    H1N1 wild virus, finding that nearly six percent of them had also suffered a thrombotic vascular
    event. See Bunce at e1. The conclusion of the study was that although infection with the H1N1
    virus “did not appear to be associated with higher rates of vascular complications than has
    previously been reported among critically ill patients,” nevertheless “the development of massive
    venous thrombotic events and clinically significant arterial thrombosis . . . suggests the possibility
    of pH1N1-associated hypercoagulability and endothelial activation and/or dysfunction in affected
    individuals.” Id. at e3. The Wiseman article concluded that two types of cytokines (IL-6 and TNF
    alpha) are associated with acute stroke compared with lacunar strokes.10 See generally Wiseman.
    And Kimura observed an increase in platelets (that contribute to blood clots) on the first day after
    a process of administration of IL-1beta in mice over a multi-day period had concluded. See
    generally Kimura.
    Dr. Axelrod also attempted to distinguish literature suggesting the flu vaccine can actually
    reduce the risk of stroke. See H. Lin, et al., Association of Influenza Vaccination and Reduced Risk
    of Stroke Hospitalization Among the Elderly: A Population-based Case-control Study, 11 Int. J.
    10
    Lacunar strokes are a result of lacunar (small pit or hollow cavity) infarcts, and most commonly cause “pure motor
    hemiparesis, ataxic hemiparesis, pure sensory stroke, sensorimotor stroke, and clumsy-hand dysarthria.” Dorland’s at
    1786.
    7
    Environmental Research and Public Health 36369 (2014), filed as Ex. 9-F (ECF No. 21-6) (“Lin”).
    He did so by noting that individuals like Mr. Hayward who had suffered a stroke within two weeks
    of vaccination had been excluded from the Lin study, thus rendering it inapplicable given the short
    timeframe at issue. Lin at 3. Dr. Axelrod otherwise referred to Bunce, noting that it showed a
    statistically significant minority (slightly less than six percent) also suffered a thrombotic vascular
    event. See Bunce at e14. Accordingly, Dr. Axelrod concluded that Petitioner could have
    experienced an innate response to the flu vaccination resulting in an increased production of
    cytokines sufficient to have caused Petitioner’s injuries. Axelrod Rep. at 3.
    B.      Dr. Marcel Kinsbourne
    Dr. Kinsbourne prepared Petitioner’s other expert report. See Report, dated March 24,
    2017, filed as Ex. 11 (ECF No. 30-1) (“Kinsbourne Rep.”). No CV was filed, but Dr. Kinsbourne
    has testified many times in the Program (and several times before me). Decisions from such cases
    consistently confirm that he is board certified in pediatrics, received his medical degree in England,
    and has been licensed to practice medicine in North Carolina since 1967. See, e.g., Strong v. Sec’y
    of Health & Human Servs., No. 15-1108, 
    2018 WL 1125666
    , at *6 (Fed. Cl. Spec. Mstr. Jan. 12,
    2018); McCollum v. Sec’y of Health & Human Servs., No. 14-790V, 
    2017 WL 5386613
    , at *6
    (Fed. Cl. Spec. Mstr. Sept. 15, 2017), mot. for review den’d, 
    133 Fed. Cl. 735
     (2017), appeal
    docketed, No. 18-1623 (Fed. Cir. Feb. 28, 2018). From 1967 to 1974, Dr. Kinsbourne served as an
    associate professor in pediatrics and neurology and a senior research associate at Duke University
    Medical Center before holding a series of academic positions, including professorships in
    pediatrics, neurology, and psychology. His clinical experience includes serving as a senior staff
    physician in Ontario from 1974-1980, and a clinical associate in neurology at Massachusetts
    General Hospital from 1981-1991, although (as noted in other cases) many years have passed since
    he regularly saw patients. Strong, 
    2018 WL 1125666
    , at *6. It has not been demonstrated in this
    case that Dr. Kinsbourne has any more direct expertise with the injury at issue than Dr. Axelrod.
    Dr. Kinsbourne’s opinion begins with a review of Mr. Hayward’s chronological medical
    history pertinent to the claim asserted herein. Kinsbourne Rep. at 1-2. He then proposes that prior
    to suffering from his first stroke, Petitioner had experienced an asymptomatic brain infarction,
    known as a “silent stroke.” 
    Id. at 3
    . Dr. Kinsbourne described silent strokes as occurring in about
    half of elderly patients, and causing no symptoms despite their presence on imaging tests. Id.; K.
    Karia, et al., ‘Silent’ Cerebral Infarction is Associated with Hypercoagulability, Endothelial Cell
    Damage and High Lp(a) Levels in Elderly Japanese, 16 Arteriosclerosis, Thrombosis and Vascular
    Biology, 734 (1996), filed as Ex. 11-E (ECF No. 30-6); S. Kobayashi, et al., Subcortical Silent
    Brain Infarction as a Risk Factor for Clinical Stroke, 28 Stroke 1932 (1997), filed as Ex. 11-F
    (ECF No. 30-7); S. Vermeer, et al., Silent Brain Infarcts And The Risk Of Dementia And Cognitive
    Decline, 348 New England J. Medicine 1215 (2003), filed as Ex. 11-L (ECF No. 31-4). Evidence
    of Petitioner’s prior brain infarctions could be seen from neuroimaging. Kinsbourne Rep. at 3; Ex.
    6 at 13.
    8
    Relying on Dr. Axelrod’s opinion about the harmful capacity of proinflammatory
    cytokines, Dr. Kinsbourne opined that Petitioner’s underlying silent strokes were aggravated by
    the flu vaccine, causing him to suffer from his first “clinically overt” stroke hours after vaccination.
    Kinsbourne Rep. at 5. Dr. Kinsbourne reiterated the points made by Dr. Axelrod to distinguish the
    Lin article, and referenced several additional pieces of medical literature that supported the concept
    that the flu vaccine, through upregulation of cytokines, could create an inflammatory environment
    ripe for embolism sufficient to result in stroke. 
    Id. at 5-6
    ; see also M. Tsai, et al., Effect of Influenza
    Vaccine on Markers of Inflammation and Lipid Profile, 145 Translational Research 323 (2005),
    filed as Ex. 11-K (ECF No. 31-3); V. DiNapoli, et al., Age Exaggerates Proinflammatory Cytokine
    Signaling and Truncates STAT3 Signaling Following Ischemic Stroke in the Rat, 170 Neuroscience
    633 (2010), filed as Ex. 11-B (ECF No. 30-3).
    Although Dr. Kinsbourne cited medical literature that silent strokes can be exacerbated by
    infection, he was somewhat conclusory in proposing that the phenomenon was occurring in
    Petitioner. Rather, Dr. Kinsbourne relied heavily on the lack of evidence of an alternate cause, as
    well as the timing of Petitioner’s stroke (occurring hours after vaccination) for his opinion that
    Petitioner’s injury was vaccine-caused. Kinsbourne Rep. at 5.
    C.      Dr. Thomas Leist
    Respondent filed two reports from Dr. Leist, Professor of Neurology at Thomas Jefferson
    University and Chief of the Division of Clinical Neuroimmunology at Jefferson University
    Hospitals. See Ex. A, filed June 28, 2016 (ECF No. 22-1) (“First Leist Rep.”); Ex. C, filed June
    20, 2017 (ECF No. 32-1) (“Second Leist Rep.”).
    Dr. Leist attended the University of Zurich, where he obtained his Ph.D. in immunology
    and biochemistry as well as a post-doctorate degree in experimental pathologies. Ex. B (Dr. Leist’s
    CV), filed on June 28, 2016 (ECF No. 22-6). He also completed a post-doctorate at the University
    of California, Los Angeles and attended medical school in the United States at the University of
    Miami. 
    Id.
     He then completed a residency in neurology at Cornell University before becoming a
    fellow at the National Institute of Health. 
    Id. at 2
    . Dr. Leist is board certified in neurology and
    currently serves as a professor of neurology at Thomas Jefferson University in Philadelphia,
    Pennsylvania as well as directing the MS center and guiding the MS or the neuro-immunology
    fellowship program. 
    Id. at 1
    .
    Dr. Leist’s overall opinion is that Petitioner was suffering from an ongoing prothrombotic
    condition that existed prior to his vaccination and was responsible for Petitioner’s post-vaccination
    stroke. First Leist Rep. at 2-3. In support of this opinion, Dr. Leist referenced the imaging results
    from the CT scan performed the night of vaccination, and the MRI performed the day after
    vaccination (which in particular observed indicia suggesting that the preexisting “silent” stroke
    Petitioner had experienced was itself embolic in nature – something the radiologist performing the
    MRI had proposed). 
    Id. at 2
    . It was therefore most likely that the preexisting abnormalities seen
    on Petitioner’s imaging caused the strokes he suffered. 
    Id. at 6, 7
    .
    9
    Dr. Leist addressed what he understood to be a cornerstone of Dr. Axelrod’s opinion -- that
    vaccination can stimulate cytokine production that can in turn induce prothrombotic conditions.
    First Leist Rep. at 3. To rebut these points, Dr. Leist attempted to distinguish many of the articles
    cited by Dr. Axelrod, pointing out that they either did not involve the flu vaccine, or did not
    demonstrate a trustworthy causal connection between any kind of vaccination and thrombotic
    disease/stroke. 
    Id. at 3-5
    .
    Dr. Leist also discussed the relevance of certain literature, like Lin, suggesting that the flu
    vaccine actually diminished the likelihood of stroke. As Dr. Axelrod noted, Lin had excluded from
    the study those patients who had recently (within the last two weeks) suffered a stroke. But Dr.
    Leist pointed out that Lin actually indicated that this subset of individuals were not included
    because they likely were not fully immunized if they suffered a stroke within two weeks of
    vaccination – suggesting that the immunologic process involved could not be completed in as short
    a time as Petitioner herein alleges. First Leist Rep. at 4; Lin at 3. In addition, Lin’s authors went
    so far as to state that although “[s]ome studies have suggested a link between influenza and stroke-
    related events . . . this relationship has not been well characterized.” Lin at 3645 (emphasis added).
    Besides challenging the cytokine upregulation aspect of Dr. Axelrod’s theory, Dr. Leist
    also attacked the portion of the theory attempting to connect upregulation with a pro-thrombotic
    environment. To that end, Dr. Leist cited a study that showed that patients at risk for a thrombotic
    event who underwent treatments that induce the production of cytokines (such as peripheral blood
    stem cell mobilization with a stimulating factor) in fact displayed no evidence of any such events
    within their first 24 hours of treatment. First Leist Rep. at 6, citing H. Naina, et al., Low Risk of
    Symptomatic Venous Thromboembolic Events During Growth Factor Administration for PBSC
    Mobilization, 46 Bone Marrow Transplantation 291 (2011), filed as Ex. A.4 (ECF No. 22-5)
    (“Naina”). That timeframe is what Petitioner alleges herein is a medically acceptable period for
    the development of a vaccine-induced cytokine storm resulting in stroke.
    Dr. Leist also noted deficiencies or limitations in the literature referenced by Dr. Axelrod
    in an effort to connect cytokines to stroke. For example, he noted that although Kimura had
    demonstrated an increase in platelets following an increase in the IL-1 beta cytokine day one after
    injection, the “one day after” was actually four days after the first cytokine injections in the
    experiment (as the tested mice were injected five times every 12 hours for several days). First Leist
    Rep. at 5. Dr. Leist also noted that Wiseman’s authors did not make a causal connection between
    cytokines and stroke; rather Wiseman only measured the cytokine levels after the stroke occurred,
    thereby only establishing an association rather than a causal relationship. 
    Id. at 4-5
    .
    Dr. Leist’s second report reacted to Dr. Kinsbourne’s opinion. In particular, Dr. Leist
    discussed Dr. Kinsbourne’s contentions that Petitioner’s preexisting subacute stroke condition was
    ongoing but exacerbated by the flu vaccine. As Dr. Leist explained, the preexisting strokes
    discovered after vaccination were best understood not as a “subclinical” condition, but as
    10
    “asymptomatic” events attributable to a preexisting “procoagulant state.” Second Leist Rep. at 5.
    The earlier strokes did not result in clinically obvious symptoms, he reasoned, due to “the location
    of the subacute strokes and the nature of the brain function that these areas supported.” 
    Id.
    (emphasis added).
    Similar to his approach with the literature cited by Dr. Axelrod, Dr. Leist also listed each
    of the articles relied on by Dr. Kinsbourne to show that they were insufficient to support
    Petitioner’s theory. Second Leist Rep. at 2-4. In particular, Dr. Leist noted that “[n]one of the
    articles referenced by Dr. Kinsbourne links influenza vaccine directly with a prothrombotic state
    and none of the articles supports petitioner’s theory that immune mechanisms induced in response
    to influenza vaccination could cause blood clots within hours of immunization.” 
    Id. at 5
    .
    Dr. Leist also reiterated the point from his first report that the flu vaccine was not
    reasonably associated with stroke generally. On the contrary – he stressed literature finding that
    the flu vaccine was associated with a decreased risk of stroke. Second Leist Rep. at 4; First Leist
    Rep. at 4; Pet. Ex. 4 at 157-59; P. Lavallée, et al., Association Between Influenza Vaccination and
    Reduced Risk of Brain Infection, 33 Stroke 513 (2001), filed as Ex. A.3 (ECF No. 22-4) (French
    case study of 90 patients older than 60 years of age admitted to hospital for brain
    infarction)(“Lavallée”). He also noted that none of Petitioner’s physicians attributed his stroke to
    the flu vaccine, even after Petitioner had specifically raised it with them as a potential explanation
    for his condition. Second Leist Rep. at 5.
    III.   PROCEDURAL HISTORY AND PARTIES’ ARGUMENTS
    As noted above, this action was initiated in January 2015. Petition at 1. Approximately six
    months later, the statement of completion was filed (ECF No. 12), followed not long thereafter by
    Respondent’s Rule 4(c) Report on September 28, 2015 (ECF No. 13). The parties then began the
    process of obtaining expert reports, which was not completed until June 20, 2017.
    At a status conference, I proposed (given the nature of the allegations and facts herein) that
    the matter could be most efficiently resolved on the papers rather than at a hearing. The parties
    subsequently filed a joint status report indicating that they would like to have the case decided on
    a motion for a ruling on the record, and proposed a briefing schedule to do so. See Joint Status
    Report, dated July 27, 2017 (ECF No. 33). Accordingly, I set the deadlines the parties suggested,
    and the briefs were timely filed. (ECF Nos. 34-37). The matter is now ripe for a decision.
    Petitioner’s Argument
    Petitioner relies on the immunological conclusions of Dr. Axelrod that 1) proinflammatory
    cytokines increase within the first six hours of the flu vaccination; 2) the H1N1 flu vaccine can
    cause inflammation leading to heart conditions; and 3) certain cytokines (IL-1 beta, IL-6, and TNF-
    alpha) are associated with heart conditions and/or stroke due to thrombosis. See Mot. at 7. Those
    11
    conclusions, in concert with Dr. Kinsbourne’s theory, thus support Petitioner’s argument that his
    receipt of the flu vaccine caused inflammation (a risk factor for stroke), which in turn worsened
    his existing infarct in his right cerebral hemisphere (previously subclinical or a “silent stroke”),
    thereafter causing a full ischemic stroke within hours of his vaccination. 
    Id. at 8
    .
    Additional support for Petitioner’s argument came from medical literature noting that one
    third of ischemic strokes are preceded by an infection. Mot. at 9; C. Hedley & S. Emsley, Acute
    Ischemic Stroke and Infection: Recent and Emerging Concepts, 7 Lancet Neurology 341 (2008),
    filed as Ex. 11-D (ECF No. 30-5). While an infection may not be directly responsible for the stroke,
    it is responsible for the inflammatory reaction triggered by the body that encourages a thrombotic
    environment. Mot. at 9. In his case, Petitioner alleges, he suffered an ischemic stroke as a result of
    an inflammatory response caused by his flu vaccination. Thus, his previously sub-acute “silent
    strokes” were significantly aggravated. 
    Id. at 11
    .
    Petitioner’s reply restated the medical history and theory of causation set forth in the
    motion for a ruling, but added that the present case presents a rare vaccine injury, thereby excusing
    the lack of more direct evidence supportive of an association between the flu vaccine and stroke.
    See Petitioner’s Reply, dated Nov. 12, 2017 (ECF No. 37) (“Reply”). The Reply also attempted to
    rebut some of Respondent’s arguments about Dr. Kinsbourne’s opinion, albeit mainly by
    recopying the summary Dr. Kinsbourne put in his expert report. 
    Id. at 8
    .
    Respondent’s Argument
    Respondent argues that Petitioner has failed to establish that he suffered a significant
    aggravation of his preexisting thromboembolic condition, and has not demonstrated that the flu
    vaccine, rather than the natural course of the preexisting condition, was responsible for his post-
    vaccination condition. Opp. at 15. In reaction to Petitioner’s assertion that significant aggravation
    was shown by the mere fact that Petitioner’s sub-acute “silent strokes” became symptomatic post-
    vaccination, Respondent pointed to Dr. Kinsbourne’s own literature that silent strokes are usually
    associated with future strokes (regardless of intervening vaccination). 
    Id. at 16
    , Second Leist Rep.
    at 3.
    Respondent went on to dismiss the theory proposed by Drs. Axelrod and Kinsbourne,
    arguing that it was not adequately supported by reliable medical literature. Opp. at 16. Rather, the
    literature cited by Petitioner to support his theory at best showed associations between wild
    infections or other vaccinations and CVA – but not a flu vaccine comparable to that received by
    Petitioner. 
    Id. at 16-17
    . Respondent also pointed to Dr. Leist’s contention that infections are
    irrelevant to causation in this instance because Petitioner received a flu vaccine that was not live,
    making it incapable of infecting cells. 
    Id. at 17
    ; First Leist Rep. at 3. And Respondent noted that
    some literature had actually found that the flu vaccine was associated with a reduced risk of stroke
    hospitalization, because it lowered the incidence of infection that could be causal in the first place.
    Opp. at 18.
    12
    At bottom, Respondent maintained that it cannot be shown that Petitioner’s vaccination
    was the cause of his CVA. Opp. at 19-20. Respondent instead relied on Dr. Leist’s opinion that
    Petitioner had a preexisting propensity for pulmonary embolism, and that this was the most likely
    cause of the post-vaccination stroke that Petitioner experienced. 
    Id. at 20
    . In addition, Respondent
    argued that onset occurring within 12 hours of vaccination was contrary to the findings of medical
    literature like Naina, which found no cases of stroke within 24 hours of a treatment that specifically
    induces cytokine production in at-risk individuals. 
    Id. at 22
    .
    IV.      APPLICABLE LEGAL STANDARDS
    A.       Claimant’s Burden in Vaccine Program Cases
    To receive compensation in the Vaccine Program, a petitioner must prove either: (1) that
    he suffered a “Table Injury” – i.e., an injury falling within the Vaccine Injury Table –
    corresponding to one of the vaccinations in question within a statutorily prescribed period of time
    or, in the alternative, (2) that his illnesses were actually caused by a vaccine (a “Non-Table
    Injury”). See Sections 13(a)(1)(A), 11(c)(1), and 14(a), as amended by 
    42 C.F.R. § 100.3
    ; §
    11(c)(1)(C)(ii)(I); see also Moberly v. Sec’y of Health & Human Servs., 
    592 F.3d 1315
    , 1321 (Fed.
    Cir. 2010); Capizzano v. Sec’y of Health & Human Servs., 
    440 F.3d 1317
    , 1320 (Fed. Cir. 2006).11
    In this case, Petitioner does not assert a Table claim.
    For both Table and Non-Table claims, Vaccine Program petitioners bear a “preponderance
    of the evidence” burden of proof. Section 13(1)(a). That is, a petitioner must offer evidence that
    leads the “trier of fact to believe that the existence of a fact is more probable than its nonexistence
    before [he] may find in favor of the party who has the burden to persuade the judge of the fact’s
    existence.” Moberly, 
    592 F.3d at
    1322 n.2; see also Snowbank Enter. v. United States, 
    6 Cl. Ct. 476
    , 486 (1984) (mere conjecture or speculation is insufficient under a preponderance standard).
    Proof of medical certainty is not required. Bunting v. Sec’y of Health & Human Servs., 
    931 F.2d 867
    , 873 (Fed. Cir. 1991). In particular, a petitioner must demonstrate 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 & Human Servs., 
    165 F.3d 1344
    ,
    1352-53 (Fed. Cir. 1999)); Pafford v. Sec’y of Health & Human Servs., 
    451 F.3d 1352
    , 1355 (Fed.
    Cir. 2006). A petitioner may not receive a Vaccine Program award based solely on his assertions;
    rather, the petition must be supported by either medical records or by the opinion of a competent
    physician. Section 13(a)(1).
    In attempting to establish entitlement to a Vaccine Program award of compensation for a
    Non-Table claim (which is the kind of claim asserted in this matter), a petitioner must satisfy all
    11
    Decisions of special masters (some of which I reference in this ruling) constitute persuasive but not binding
    authority. Hanlon v. Sec’y of Health & Human Servs., 
    40 Fed. Cl. 625
    , 630 (1998). By contrast, Federal Circuit rulings
    concerning legal issues are binding on special masters. Guillory v. Sec’y of Health & Human Servs., 
    59 Fed. Cl. 121
    ,
    124 (2003), aff’d, 104 F. App’x 712 (Fed. Cir. 2004); see also Spooner v. Sec’y of Health & Human Servs., No. 13-
    159V, 
    2014 WL 504728
    , at *7 n.12 (Fed. Cl. Spec. Mstr. Jan. 16, 2014).
    13
    three of the elements established by the Federal Circuit in Althen v. Sec’y of Health & Human
    Servs., 
    418 F.3d 1274
    , 1278 (Fed. Cir. 2005): “(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.”
    Each of the Althen prongs requires a different showing. Under Althen prong one, petitioners
    must provide a “reputable medical theory,” demonstrating that the vaccine received can cause the
    type of injury alleged. Pafford, 451 F.3d at 1355-56 (citations omitted). To satisfy this prong, the
    petitioner’s theory must be based on a “sound and reliable medical or scientific explanation.”
    Knudsen v. Sec’y of Health & Human Servs., 
    35 F.3d 543
    , 548 (Fed. Cir. 1994). Such a theory
    must only be “legally probable, not medically or scientifically certain.” 
    Id. at 549
    .
    Petitioners may satisfy the first Althen prong without resort to medical literature,
    epidemiological studies, demonstration of a specific mechanism, or a generally accepted medical
    theory. Andreu v. Sec’y of Health & Human Servs., 
    569 F.3d 1367
    , 1378-79 (Fed. Cir. 2009) (citing
    Capizzano, 
    440 F.3d at 1325-26
    ). Special masters, despite their expertise, are not empowered by
    statute to conclusively resolve what are essentially thorny scientific and medical questions, and
    thus scientific evidence offered to establish Althen prong one is viewed “not through the lens of
    the laboratorian, but instead from the vantage point of the Vaccine Act’s preponderant evidence
    standard.” 
    Id. at 1380
    . Accordingly, special masters must take care not to increase the burden
    placed on petitioners in offering a scientific theory linking vaccine to injury. Contreras v. Sec’y of
    Health & Human Servs., 
    121 Fed. Cl. 230
    , 245 (2015) (“[p]lausibility . . . in many cases may be
    enough to satisfy Althen prong one” (emphasis in original)). But this does not negate or reduce a
    petitioner’s ultimate burden to establish his overall entitlement to damages by preponderant
    evidence. W.C. v. Sec’y of Health & Human Servs., 
    704 F.3d 1352
    , 1356 (Fed. Cir. 2013) (citations
    omitted).
    The second Althen prong requires proof of a logical sequence of cause and effect, usually
    supported by facts derived from a petitioner’s medical records. Althen, 
    418 F.3d at 1278
    ; Andreu,
    
    569 F.3d at 1375-77
    ; Capizzano, 
    440 F.3d at 1326
    ; Grant v. Sec’y of Health & Human Servs., 
    956 F.2d 1144
    , 1148 (Fed. Cir. 1992). In establishing that a vaccine “did cause” injury, the opinions
    and views of the injured party’s treating physicians are entitled to some weight. Andreu, 
    569 F.3d at 1367
    ; Capizzano, 
    440 F.3d at 1326
     (“medical 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 particularly
    trustworthy evidence, since they are created contemporaneously with the treatment of the patient.
    Cucuras v. Sec’y of Health & Human Servs., 
    993 F.2d 1525
    , 1528 (Fed. Cir. 1993).
    However, medical records and/or statements of a treating physician’s views do not per se
    bind the special master to adopt the conclusions of such an individual, even if they must be
    considered and carefully evaluated. Section 13(b)(1) (providing that “[a]ny such diagnosis,
    14
    conclusion, judgment, test result, report, or summary shall not be binding on the special master or
    court”); Snyder v. Sec’y of Health & Human Servs., 
    88 Fed. Cl. 706
    , 746 n.67 (2009) (“there is
    nothing . . . that mandates that the testimony of a treating physician is sacrosanct—that it must be
    accepted in its entirety and cannot be rebutted”). As with expert testimony offered to establish a
    theory of causation, the opinions or diagnoses of treating physicians are only as trustworthy as the
    reasonableness of their suppositions or bases. The views of treating physicians should also be
    weighed against other, contrary evidence also present in the record – including conflicting opinions
    among such individuals. Hibbard v. Sec’y of Health & Human Servs., 
    100 Fed. Cl. 742
    , 749 (2011)
    (not arbitrary or capricious for special master to weigh competing treating physicians’ conclusions
    against each other), aff'd, 
    698 F.3d 1355
     (Fed. Cir. 2012); Caves v. Sec’y of Health & Human
    Servs., 
    100 Fed. Cl. 119
    , 136 (2011), aff'd, 463 F. App’x 932 (Fed. Cir. 2012); Veryzer v. Sec’y of
    Health & Human Servs., No. 06-522V, 
    2011 WL 1935813
    , at *17 (Fed. Cl. Spec. Mstr. Apr. 29,
    2011), mot. for review den’d, 
    100 Fed. Cl. 344
    , 356 (2011), aff’d without opinion, 475 Fed. App’x
    765 (Fed. Cir. 2012).
    The third Althen prong requires establishing a “proximate temporal relationship” between
    the vaccination and the injury alleged. Althen, 
    418 F.3d at 1281
    . That term has been equated to the
    phrase “medically-acceptable temporal relationship.” 
    Id.
     A petitioner must offer “preponderant
    proof that the onset of symptoms occurred within a timeframe which, given the medical
    understanding of the disorder’s etiology, it is medically acceptable to infer causation.” Bazan v.
    Sec’y of Health & Human Servs., 
    539 F.3d 1347
    , 1352 (Fed. Cir. 2008). The explanation for what
    is a medically acceptable timeframe must also coincide with the theory of how the relevant vaccine
    can cause an injury (Althen prong one’s requirement). 
    Id. at 1352
    ; Shapiro v. Sec’y of Health &
    Human Servs., 
    101 Fed. Cl. 532
    , 542 (2011), recons. den’d after remand, 
    105 Fed. Cl. 353
     (2012),
    aff’d mem., 
    2013 WL 1896173
     (Fed. Cir. 2013); Koehn v. Sec’y of Health & Human Servs., No.
    11-355V, 
    2013 WL 3214877
     (Fed. Cl. Spec. Mstr. May 30, 2013), mot. for review den’d (Fed. Cl.
    Dec. 3, 2013), aff’d, 
    773 F.3d 1239
     (Fed. Cir. 2014).
    B.      Standard for Significant Aggravation Claim
    In this matter, Petitioner offers a parallel theory that the vaccines significantly aggravated
    a preexisting condition—CVA and a thromboembolic condition. Mot. at 1. Where a petitioner so
    alleges, the Althen test is expanded, and the petitioner has additional evidentiary burdens to satisfy.
    See generally Loving v. Sec’y of Health & Human Servs., 
    86 Fed. Cl. 135
    , 144 (2009). In Loving,
    the Court of Federal Claims combined the Althen test with the test from Whitecotton v. Sec’y of
    Health & Human Servs., 
    81 F.3d 1099
    , 1107 (Fed. Cir. 1996), which related to on-Table significant
    aggravation cases. The resultant “significant aggravation” test has six components, which are:
    (1) the person’s condition prior to administration of the vaccine, (2) the person’s current
    condition (or the condition following the vaccination if that is also pertinent), (3) whether
    the person’s current condition constitutes a ‘significant aggravation’ of the person’s
    condition prior to vaccination, (4) a medical theory causally connecting such a
    significantly worsened condition to the vaccination, (5) a logical sequence of cause and
    effect showing that the vaccination was the reason for the significant aggravation, and (6)
    15
    a showing of a proximate temporal relationship between the vaccination and the
    significant aggravation.
    Loving, 86 Fed. Cl. at 144; see also W.C. v. Sec’y of Health & Human Servs., 
    704 F.3d 1352
    , 1357
    (Fed. Cir. 2013) (holding that “the Loving case provides the correct framework for evaluating off-
    table significant aggravation claims”). In effect, the last three prongs of the Loving test correspond
    to the three Althen prongs.
    Within the Loving analysis, it is necessary to evaluate the likely natural course of the
    petitioner’s preexisting disease, in order to determine whether the vaccine made the petitioner
    worse than he would have been but for the vaccination. Locane v. Sec’y of Health & Human Servs.,
    
    685 F.3d 1375
    , 1381-82 (Fed. Cir. 2012) (upholding special master’s determination that petitioner
    had failed to carry her burden of proof in establishing that her preexisting injury was worsened by
    the relevant vaccine); Hennessey v. Sec’y of Health & Human Servs., No. 01-190V, 
    2009 WL 1709053
    , at *41-42 (Fed. Cl. Spec. Mstr. May 29, 2009), mot. for review den’d, 91 Fed. Cl 126
    (2010). In other words, the critical point of examination is “whether the change for the worse in
    [petitioners] clinical presentation was aggravation or a natural progression” of the underlying
    condition. Hennessey, 
    2009 WL 1709053
    , at *42.12
    The mere fact a vaccine might “trigger” a transitory negative response in an individual with
    an underlying condition is not proof of worsening if that individual would be expected to
    experience a similar course regardless. Faoro v. Sec’y of Health &Human Servs., No. 10-704V,
    
    2016 WL 675491
    , at *27 (Fed. Cl. Spec. Mstr. Jan. 29, 2016), mot. rev. den’d, 
    128 Fed. Cl. 61
    (Fed. Cl. Apr. 11, 2016) (finding that “the vaccinations would not have changed her clinical course
    and thus, the vaccinations did not significantly aggravate her preexisting condition”). This point
    12
    There is some ambiguity as to whether petitioner bears the burden of establishing this worsening. Prior to Loving,
    prevailing law required in part that the special master “assess the individual’s current condition after the administration
    of the vaccine . . . predict the individual’s condition had the vaccine not been administered, and . . . compare the
    individual’s current condition with the predicted condition had the vaccine not been administered.” Misasi v. Sec’y of
    Health & Human Servs., 
    23 Cl. Ct. 322
    , 325 (1991). The Federal Circuit thereafter (in O’Conner v. Sec’y of Health
    and Human Services, 
    24 Cl. Ct. 428
     (1991), aff’d 
    975 F.2d 868
     (Fed. Cir. 1992)) clarified that Misasi was not to be
    interpreted as increasing Petitioner’s burden, but that in significant aggravation cases Respondent’s burden (once a
    petitioner had made her prima facie case) remained to show an alternative cause – and that this could be satisfied by
    demonstrating that the natural progression of the pre-existing condition accounted for the petitioner’s post-vaccine
    condition. 
    Id. at 430, n.2
    .
    Although neither Whitecotton nor Loving addressed Misasi or O’Connor in their analyses, the Loving test appears to
    embrace the same overall approach. Nevertheless, the Federal Circuit has upheld the determinations of special masters
    that worsening was not demonstrated by a petitioner in connection with her overall preponderant burden of proof. See,
    e.g., Snyder/Harris v. Sec'y of Health & Human Servs., 553 Fed. App’x 994, 999-1000 (Fed. Cir. 2014); Locane, 685
    F.3d at 1381-82. This is consistent with the fact (well recognized by controlling precedent) that “worsening” evidence
    relevant to Respondent’s alternative cause burden may reasonably by evaluated by a special master in determining the
    success of a petitioner’s prima facie showing. Snyder/Harris, 553 Fed. App’x at 1000, quoting Stone v. Sec’y of Health
    & Human Servs., 
    676 F.3d 1373
    , 1380 (Fed. Cir. 2012) (“no evidence should be embargoed from the special master’s
    consideration simply because it is also relevant to another inquiry under the statute”); see also de Bazan v. Sec’y of
    Health & Human Servs., 
    539 F.3d 1347
    , 1353 (Fed. Cir. 2008) (“[t]he government, like any defendant, is permitted
    to offer evidence to demonstrate the inadequacy of the petitioner’s evidence on a requisite element of the petitioner’s
    case-in-chief”).
    16
    was emphasized in a subcategory of Program cases involving the claim that a child’s Dravet
    syndrome (a rare seizure disorder now understood to be caused by the SCN1A gene mutation) was
    significantly aggravated by vaccination. Faoro, 
    2016 WL 675491
    , at *1. In such cases, special
    masters have repeatedly determined that petitioners failed to show that a child’s expected outcome
    would have been different but-for the vaccination – even though it was not disputed that the child’s
    first major seizure had in fact been triggered by vaccination. 
    Id. at *2
     (“[a]lthough H.E.F.’s
    vaccinations may have caused a low-grade fever or otherwise triggered her first seizure, neither
    the initial seizure nor her vaccinations caused or significantly aggravated her Dravet syndrome and
    resulting neurological complications”); see also Snyder/Harris v. Sec'y of Health & Human Servs.,
    553 Fed. App’x 994 (Fed. Cir. 2014) (special master was not arbitrary in finding that petitioners’
    expert failed to show that the child’s outcome would have been different had he not received the
    vaccinations at issue).
    C.      Law Governing Factual Determinations
    The process for making determinations in Vaccine Program cases regarding factual issues
    begins with consideration of the medical records. Section 11(c)(2). The special master is required
    to consider “all [] relevant medical and scientific evidence contained in the record,” including “any
    diagnosis, conclusion, medical judgment, or autopsy or coroner’s report which is contained in the
    record regarding the nature, causation, and aggravation of the petitioner’s illness, disability, injury,
    condition, or death,” as well as “the results of any diagnostic or evaluative test which are contained
    in the record and the summaries and conclusions.” Section 13(b)(1)(A). The special master is then
    required to weigh the evidence presented, including contemporaneous medical records and
    testimony. See Burns v. Sec’y of Health & Human Servs., 
    3 F.3d 415
    , 417 (Fed. Cir. 1993) (it is
    within the special master’s discretion to determine whether to afford greater weight to
    contemporaneous medical records than to other evidence, such as oral testimony surrounding the
    events in question that was given at a later date, provided that such a determination is evidenced
    by a rational determination).
    Medical records that are created contemporaneously with the events they describe are
    presumed to be accurate and “complete” (i.e., presenting all relevant information on a patient’s
    health problems). Cucuras, 
    993 F.2d at 1528
    ; Doe/70 v. Sec’y of Health & Human Servs., 
    95 Fed. Cl. 598
    , 608 (2010) (“[g]iven the inconsistencies between petitioner’s testimony and his
    contemporaneous medical records, the special master’s decision to rely on petitioner’s medical
    records was rational and consistent with applicable law”), aff’d, Rickett v. Sec’y of Health &
    Human Servs., 468 F. App’x 952 (Fed. Cir. 2011) (non-precedential opinion). This presumption is
    based on the linked propositions that (i) sick people visit medical professionals; (ii) sick people
    honestly report their health problems to those professionals; and (iii) medical professionals record
    what they are told or observe when examining their patients in as accurate a manner as possible,
    so that they are aware of enough relevant facts to make appropriate treatment decisions. Sanchez
    v. Sec’y of Health & Human Servs., No. 11-685V, 
    2013 WL 1880825
    , at *2 (Fed. Cl. Spec. Mstr.
    Apr. 10, 2013); Cucuras v. Sec'y of Health & Human Servs., 
    26 Cl. Ct. 537
    , 543 (1992), aff’d, 
    993 F.2d 1525
     (Fed. Cir. 1993) (“[i]t strains reason to conclude that petitioners would fail to accurately
    17
    report the onset of their daughter’s symptoms. It is equally unlikely that pediatric neurologists,
    who are trained in taking medical histories concerning the onset of neurologically significant
    symptoms, would consistently but erroneously report the onset of seizures a week after they in fact
    occurred”).
    Accordingly, if the medical records are clear, consistent, and complete, then they should
    be afforded substantial weight. Lowrie v. Sec’y of Health & Human Servs., No. 03-1585V, 
    2005 WL 6117475
    , at *20 (Fed. Cl. Spec. Mstr. Dec. 12, 2005). Indeed, contemporaneous medical
    records are generally found to be deserving of greater evidentiary weight than oral testimony –
    especially where such testimony conflicts with the record evidence. Cucuras, 
    993 F.2d at 1528
    ;
    see also Murphy v. Sec’y of Health & Human Servs., 
    23 Cl. Ct. 726
    , 733 (1991), aff'd, 
    968 F.2d 1226
     (Fed. Cir.), cert. den’d, Murphy v. Sullivan, 
    506 U.S. 974
     (1992) (citing United States v.
    United States Gypsum Co., 
    333 U.S. 364
    , 396 (1947) (“[i]t has generally been held that oral
    testimony which is in conflict with contemporaneous documents is entitled to little evidentiary
    weight.”)).
    However, there are situations in which compelling oral 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 & Human Servs., 
    69 Fed. Cl. 775
    , 779 (2006) (“like 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, 
    2005 WL 6117475
    , at *19
    (“[w]ritten records which are, themselves, inconsistent, should be accorded less deference than
    those which are internally consistent”) (quoting Murphy v. Sec’y of Health & Human Servs., 
    23 Cl. Ct. 726
    , 733 (1991), aff'd per curiam, 
    968 F.2d 1226
     (Fed. Cir. 1992)). Ultimately, a
    determination regarding a witness’s credibility is needed when determining the weight that such
    testimony should be afforded. Andreu, 
    569 F.3d at 1379
    ; Bradley v. Sec’y of Health & Human
    Servs., 
    991 F.2d 1570
    , 1575 (Fed. Cir. 1993).
    When witness testimony is offered to overcome the presumption of accuracy afforded to
    contemporaneous medical records, such testimony must be “consistent, clear, cogent, and
    compelling.” Sanchez, 
    2013 WL 1880825
    , at *3 (citing Blutstein v. Sec’y of Health & Human
    Servs., No. 90-2808V, 
    1998 WL 408611
    , at *5 (Fed. Cl. Spec. Mstr. June 30, 1998)). In
    determining the accuracy and completeness of medical records, the Court of Federal Claims has
    listed four possible explanations for inconsistencies between contemporaneously created medical
    records and later testimony: (1) a person’s failure to recount to the medical professional everything
    that happened during the relevant time period; (2) the medical professional’s failure to document
    everything reported to her or him; (3) a person’s faulty recollection of the events when presenting
    testimony; or (4) a person’s purposeful recounting of symptoms that did not exist. La Londe v.
    Sec’y Health & Human Servs., 
    110 Fed. Cl. 184
    , 203-04 (2013), aff’d, 
    746 F.3d 1334
     (Fed. Cir.
    2014). In making a determination regarding whether to afford greater weight to contemporaneous
    medical records over contrary testimony, there must be evidence that this decision was the result
    of a rational determination. Burns, 
    3 F.3d at 417
    .
    18
    D.      Analysis of Expert Testimony
    Establishing a sound and reliable medical theory often requires a petitioner to present
    expert testimony in support of his claim. Lampe v. Sec’y of Health & Human Servs., 
    219 F.3d 1357
    , 1361 (Fed. Cir. 2000). Vaccine Program expert testimony is usually evaluated according to
    the factors for analyzing scientific reliability set forth in Daubert v. Merrell Dow Pharm., Inc., 
    509 U.S. 579
    , 594-96 (1993). See Cedillo v. Sec’y of Health & Human Servs., 
    617 F.3d 1328
    , 1339
    (Fed. Cir. 2010) (citing Terran v. Sec’y of Health & Human Servs., 
    195 F.3d 1302
    , 1316 (Fed. Cir.
    1999)). “The Daubert factors for analyzing the reliability of testimony are: (1) whether a theory or
    technique can be (and has been) tested; (2) whether the theory or technique has been subjected to
    peer review and publication; (3) whether there is a known or potential rate of error and whether
    there are standards for controlling the error; and (4) whether the theory or technique enjoys general
    acceptance within a relevant scientific community.” Terran, 
    195 F.3d at
    1316 n.2 (citing Daubert,
    
    509 U.S. at 592-95
    ).
    The Daubert factors play a slightly different role in Vaccine Program cases than they do
    when applied in other federal judicial fora (such as the district courts). Daubert factors are usually
    employed by judges (in the performance of their evidentiary gatekeeper roles) to exclude evidence
    that is unreliable and/or could confuse a jury. In Vaccine Program cases, by contrast, these factors
    are used in the weighing of the reliability of scientific evidence proffered. Davis v. Sec’y of Health
    & Human Servs., 
    94 Fed. Cl. 53
    , 66-67 (2010) (“uniquely in this Circuit, the Daubert factors have
    been employed also as an acceptable evidentiary-gauging tool with respect to persuasiveness of
    expert testimony already admitted”). The flexible use of the Daubert factors to evaluate the
    persuasiveness and reliability of expert testimony has routinely been upheld. See, e.g., Snyder, 88
    Fed. Cl. at 742-45. In this matter (as in numerous other Vaccine Program cases), Daubert has not
    been employed at the threshold, to determine what evidence should be admitted, but instead to
    determine whether expert testimony offered is reliable and/or persuasive.
    Respondent frequently offers one or more experts of his own in order to rebut a petitioner’s
    case. Where both sides offer expert testimony, a special master’s decision may be “based on the
    credibility of the experts and the relative persuasiveness of their competing theories.”
    Broekelschen v. Sec’y of Health & Human Servs., 
    618 F.3d 1339
    , 1347 (Fed. Cir. 2010) (citing
    Lampe, 
    219 F.3d at 1362
    ). However, nothing requires the acceptance of an expert’s conclusion
    “connected to existing data only by the ipse dixit of the expert,” especially if “there is simply too
    great an analytical gap between the data and the opinion proffered.” Snyder, 88 Fed. Cl. at 743
    (quoting Gen. Elec. Co. v. Joiner, 
    522 U.S. 146
     (1997)); see also Isaac v. Sec’y of Health & Human
    Servs., No. 08-601V, 
    2012 WL 3609993
    , at *17 (Fed. Cl. Spec. Mstr. July 30, 2012), mot. for
    review den’d, 
    108 Fed. Cl. 743
     (2013), aff’d, 540 Fed. App’x 999 (Fed. Cir. 2013) (citing Cedillo,
    617 F.3d at 1339).
    19
    E.      Consideration of Medical Literature
    Both parties relied on several pieces of medical and scientific literature in this case in
    support of their respective positions. I have reviewed all of the medical literature submitted in this
    case, although my decision does not discuss each filed article in detail. Moriarty v. Sec’y of Health
    & Human Servs., No. 2015-5072, 
    2016 WL 1358616
    , at *5 (Fed. Cir. Apr. 6, 2016) (“[w]e
    generally presume that a special master considered the relevant record evidence even though he
    does not explicitly reference such evidence in his decision”) (citation omitted).
    F.      Determination to Resolve Case without Hearing
    The parties accepted my proposal to resolve entitlement in this case based on written
    submissions and evidentiary filings, including the expert reports filed by each side. The Vaccine
    Act and Rules not only contemplate but encourage special masters to decide petitions on the papers
    rather than via evidentiary hearing, where (in the exercise of their discretion) they conclude that
    the former means of adjudication will properly and fairly resolve the case. Section 12(d)(2)(D);
    Vaccine Rule 8(d). The choice to do so has been affirmed on appeal. See Hooker v. Sec’y of Health
    & Human Servs., No. 02-472V, 
    2016 WL 3456435
    , at *21 n.19 (Fed. Cl. Spec. Mstr. May 19,
    2016) (citing numerous cases where special masters decided on the papers in lieu of hearing and
    that decision was upheld). I am simply not required to hold a hearing in every matter, no matter
    the preferences of the parties. D’Toile v. Sec’y of Health & Human Servs., No. 15-85V, 2016
    7664475 (Fed. Cl. Spec. Mstr. Nov. 28, 2016) (deciding entitlement without hearing), mot. for
    review den’d, 
    132 Fed. Cl. 421
     (2017), aff’d, No. 2017-1982, 
    2018 WL 1750619
     (Fed. Cir. 2018);
    see also Hovey v. Sec’y of Health & Human Servs., 
    38 Fed. Cl. 397
    , 402-03 (1997) (special master
    acted within his discretion in denying evidentiary hearing); Burns, 
    3 F.3d at 417
    ; Murphy v. Sec’y
    of Health & Human Servs., No. 90-882V, 
    1991 WL 71500
    , at *2 (Ct. Cl. Spec. Mstr. Apr. 19,
    1991).
    ANALYSIS
    After careful review of the expert reports, medical records, scientific and medical literature,
    and the arguments of both sides, and taking into account parallel decisions from other Vaccine Act
    cases, I conclude that Petitioner has not established preponderant evidence in favor of his claim. I
    address the deficiencies of his argument in the order of their significance to my determination.
    A.      Petitioner Has Not Shown that the Flu Vaccine More Likely
    Than Not Was the Cause of his Stroke and Other Injuries
    Incontrovertible record evidence strongly suggests that, more likely than not, Petitioner’s
    post-vaccination stroke/CVA was causally related to the subacute strokes he had experienced
    before receiving the flu vaccine, but which were only discovered thereafter (as evidenced by the
    January 8, 2012 brain MRI). I find that Petitioner has not offered a persuasive reading of that
    record suggesting the contrary, nor have his experts established reliable explanations of that record
    that minimize the likely impact of his preexisting condition. Indeed – Dr. Kinsbourne agrees that
    20
    the record establishes that Petitioner likely had experienced “silent strokes” prior to the incident
    at issue, and that they were related to his post-vaccination injuries. The record itself also does not
    include any treater speculation that the flu vaccine caused his first clinically-observed CVA. This
    record therefore does not support the conclusion that the flu vaccine itself “caused” the subsequent
    strokes.
    B.       Petitioner’s Pre-Vaccination CVA Was Not Likely Significantly Aggravated
    By his Receipt of the Flu Vaccine
    Although there are several additional elements of the Loving test that must be met for a
    claim of significant aggravation to succeed, this case – like many – turns on the third factor, which
    involves the evaluation whether a petitioner’s preexisting condition was worsened by the vaccine.
    As discussed above, this does not merely entail determining that a petitioner was not facially “sick”
    before receiving the vaccine, but then was thereafter. Hennessey, 
    2009 WL 1709053
    , at *41-42.
    Rather (and stemming from the fact that a significant aggravation claimant inherently recognizes
    that his pre-vaccination condition has played some role in his post-vaccination state), the evidence
    must establish that the expected course of the Petitioner’s condition was worsened due to
    vaccination. 
    Id.
     The fact that a vaccine might transiently trigger a reaction that exposes the
    preexisting condition, or causes a temporary spike in symptoms, but does not otherwise cause the
    claimant’s course to deviate from what would be expected, does not by itself establish that it has
    worsened the underlying condition overall. Faoro, 
    2016 WL 675491
    , at *2.
    Here, the evidence does not support the conclusion that Petitioner’s expected health
    outcome would have been more favorable absent vaccination than what he actually experienced.
    Petitioner relies heavily on the fact that he had his most serious stroke after (albeit on the same
    day as) vaccination – the temporal relationship. However, it is an established Program principle
    that timing alone is insufficient to show causation. Grant v. Sec’y of Health & Human Servs., 
    956 F.2d 1144
    , 1148 (Fed. Cir. 1992) (“a proximate temporal association alone does not suffice to
    show a causal link between the vaccination and injury”). He offers little persuasive scientific or
    medical support for the proposition that a person with underlying “silent” strokes can be expected
    to be made worse by vaccination, and the scientific and medical evidence he offered was
    insufficient on this subject. At the same time, Dr. Leist cited some literature associating the flu
    vaccine with a decreased risk for stroke. First Leist Rep. at 4; Lavallée at 513.
    The record also does not support the conclusion that the flu vaccine worsened Petitioner’s
    subacute strokes/pro-thrombotic condition. None of Petitioner’s treaters related his vaccination to
    his subsequent stroke in the first place – and those few references to the contrary in the record
    appear only to raise the association as a speculative possibility rather than as grounds for further
    evaluation or a basis for treatment.13 The medical records otherwise do not establish a history that
    13
    For example, one record references speculation by a treater that the flu vaccine’s purported mercury content could
    have played a role in Petitioner’s subsequent strokes (Ex. 4 at 157-59), but it is a fleeting reference. Beyond that,
    Petitioner has not embraced this concept in his causation theory – and for good reason too, given the poor treatment
    such an argument (that mercury in vaccines causes injury) has received in past cases. See, e.g., Kolakowski v. Sec’y of
    21
    could be persuasively argued stands in marked contrast to what Petitioner would have experienced
    but for the flu vaccine, and instead appears consistent with what a person who had experienced an
    initial, asymptomatic stroke would likely experience in the future.
    Petitioner was unable to take advantage of his experts’ opinions (as set forth in their
    respective reports) to remedy the evidentiary deficiencies that his literature could not satisfy.
    Although Drs. Axelrod and Kinsbourne have the backgrounds necessary to offer opinions in this
    case on the causation claim at issue, neither is a specialist in CVA or embolisms, and so their
    statements about what they personally deem likely in this case but for vaccination merit somewhat
    less weight than I would give to the statements of an expert with demonstrated experience with the
    illness in question. They could not draw upon personal experience treating stroke, for example, to
    opine that the flu vaccine would likely worsen a claimant’s expected prognosis, or offer an
    interpretation of Mr. Hayward’s record as revealing a course more negative than what would have
    been expected but for the vaccine.
    C.       Petitioner Has Not Demonstrated that the Flu Vaccine Can Cause
    Stroke or CVA
    Petitioner’s causation theory proposes that the flu vaccine can induce the production of
    cytokines, thereby causing inflammation sufficient to create a favorable environment for stroke.
    Mot. at 7. I was unable to find case law helpful on this point.14 Petitioner’s experts have offered
    reliable proof (particularly certain items of scientific literature) for some components of their
    theory. The problem with this evidence is that it does not go far enough, leaving unlinked
    propositions in the overall causation “chain”, or overstating the findings for an otherwise-reliable
    item of medical/scientific literature.
    For example, Dr. Axelrod relied heavily on Kashiwagi, a study whose central purpose
    (comparing the levels of inflammatory cytokines in the sera of vaccine recipients with febrile and
    non-febrile illnesses within 24 hours of vaccination) does not shed light on whether the particular
    kinds of cytokines observed in the study (and induced after receipt of different vaccines) could
    Health & Human Servs., No. 99–625V, 
    2010 WL 5672753
    , at 140 (Fed. Cl. Spec. Mstr. Nov. 23, 2010) (concluding
    after extensive analysis that mercury-containing vaccines could not be shown to be sufficiently toxic to cause injury
    generally).
    14
    There appear to be no decisions from the Vaccine Program favorable to a petitioner in which stroke was alleged to
    have been an aspect of the petitioner’s injury. See e.g., Flores v. Sec’y of Health & Human Servs., No. 10-489V, 
    2013 WL 5587390
     (Fed. Cl. Spec. Mstr. Sept. 12, 2013) (denying entitlement for a spinal cord infarction following the
    HPV vaccine because Petitioner did not have the “critical” genetic criteria to meet the causation theory), mot. for rev.
    den’d, 
    115 Fed. Cl. 157
     (2014), aff’d, 586 Fed. App’x 588 (Fed. Cir. 2014); Carrino v. Sec’y of Health & Human
    Servs., No. 08–266V, 
    2013 WL 3328903
     (Fed. Cl. Spec. Mstr. June 6, 2013) (denying entitlement because Petitioner
    had not set forth a reliable theory to causally connect the flu vaccine to lateral medullary syndrome); Francis v. Sec’y
    of Health & Human Servs., No. 99-286V 
    2000 WL 1517676
     (Fed. Cl. Spec. Mstr. Aug. 31, 2000) (finding that
    petitioner had not met his burden in establishing that an encephalopathy occurred following the DTP vaccination
    administration precipitating a stroke); Wilson v. Sec’y of Health & Human Servs., No. 90-795V, 
    1992 WL 118955
    (Cl. Ct. May 15, 1992) (determining that there was not preponderant evidence that petitioner suffered an
    encephalopathy followed by a stroke and a brain injury after receiving the DTP vaccine).
    22
    cause the injury proposed herein (stroke/embolism/CVA). Kashiwagi at 677. Thus, however
    reliable Kashiwagi might be specifically when taken on its own terms, it alone does not provide
    the kind of preponderant evidence required for me to conclude that the flu vaccine could more
    likely than not induce a stroke via cytokine upregulation.
    More broadly, and as I have noted in other cases in which the same theory (also espoused
    by Dr. Axelrod, and also supported by citation to Kashiwagi) was offered, the theory itself - that
    vaccine-induced cytokine upregulation can incite a disease process resulting in injury - has
    significant deficiencies. See, e.g., Dean v. Sec’y of Health & Human Servs., No. 13-808V, 
    2017 WL 2926605
     (Fed. Cl. Spec. Mstr. Jun. 9, 2017) (ruling on the record that the “cytokine storm”
    theory was not a persuasive causation theory explaining Petitioner’s neurological deficits
    following the DTaP and Hib vaccines) mot. for rev. den’d, slip op. (Fed. Cl. Sept. 26, 2017); Wolf
    v. Sec’y of Health & Human Servs., No. 14-342V, 
    2016 WL 6518581
    , at *13 (Fed. Cl. Spec. Mstr.
    Sept. 15, 2016) (dismissing claim on the record after determining that the proinflammatory
    cytokine expression theory was insufficiently reliable to explain how vaccination caused
    Petitioner’s developmental impairments); Godfrey v. Sec’y of Health & Human Servs., No. 10-
    565V, 
    2015 WL 10710961
    , at *10-14 (Fed. Cl. Spec. Mstr. Oct. 27, 2015) (insufficient reliable
    scientific evidence supported proposition that cytokine upregulation induced by HPV vaccine was
    pathogenic enough to cause juvenile ankylosing spondylitis), mot. for review den’d, slip op. (Fed.
    Cl. Apr. 29, 2016).
    The concept that cytokine upregulation could encourage a disease process is rooted in the
    capacity of a vaccine to stimulate the innate immune system. For it to be persuasive from an
    evidentiary purpose, it would need to be linked to additional evidence showing when this occurs,
    with respect to what illnesses or diseases, and perhaps even that it has been observed with respect
    to any specific vaccine. It is not enough to twist the fact that increased numbers of inflammatory-
    associated cytokines have been measured in the context of certain injuries or illnesses (or are
    involved in the body’s reaction to those illnesses) into a causal relationship, without the evidence
    required to do so.
    Other literature was filed in this case in an attempt to support the argument that increased
    production of cytokines via the flu vaccination could cause a heart condition. As pointed out by
    Respondent’s expert, Dr. Leist, however, much of it involves strokes following infection with the
    wild flu virus, or a live flu vaccine, and thus involves circumstances distinct from the killed-virus
    form of the flu vaccine that Petitioner received. First Leist Rep. at 4-5; Opp. at 17. Literature was
    also offered to support the contention that there was an observed increased level of cytokines
    following a stroke - although, as Dr. Leist correctly noted, the previously-undiscovered strokes
    Mr. Hayward experienced could also be responsible for the same inflammatory markers, and in
    any event there was no evidence in this case at all measuring these markers. First Leist Rep. at 4.
    And the evidence offered to link an increase in inflammatory cytokines to a prothrombotic
    environment was unpersuasive as well - not only because the cited studies did not draw a causal
    link between cytokines and strokes/blood clots, but also because the timelines proposed by the
    23
    studies (accepting arguendo that cytokines could cause a stroke) were actually longer than the
    timeframe at issue in this case. See generally Wiseman; Kimura at 1.
    At the same time, both sides filed articles suggesting that the flu vaccine has been
    demonstrated to be protective against brain infarction, thereby further undermining Petitioner’s
    overall showing. First Leist Rep. at 3; Lin; Lavallée. While I do not find that this concept was any
    “more likely than not” proven than Petitioner’s causation theory, it raised points that needed to be
    rebutted or distinguished by Petitioner, since it tended to weaken his argument that the flu vaccine
    could be harmful to an individual who had already experienced a stroke. McCollum v. Sec’y of
    Health & Human Servs., No. 14-790V, 
    2017 WL 5386613
     (Fed. Cl. Spec. Mstr. Sept. 15, 2017)
    (even if petitioner was not required to submit epidemiological evidence in support of his claim, he
    nevertheless needed to rebut Respondent’s relevant epidemiological evidence that was contrary to
    Petitioner’s causation theory), mot. for rev. den’d, 
    35 Fed. Cl. 735
     (Dec. 21, 2017), appeal
    docketed, Fed. Cir. (Feb. 28, 2018). If evidence exists establishing that the flu vaccine might be
    beneficial to similarly-situated individuals, it behooved Petitioner to deal with it persuasively.
    Petitioner ultimately relies mostly on Petitioner’s injury occurring so soon after vaccination
    to push his causation theory over the line. Dr. Axelrod’s expertise, while sufficient to explain the
    theory, is not enough (based on his actual practice and experience) to give it the ballast needed for
    me to find it preponderantly supported. And while individual items of literature offered in support
    were scientifically reliable, the overall causation “chain” had too many missing, or weakly
    substantiated, links. Petitioner has not met the Program’s preponderant evidentiary standard with
    respect to the first Althen prong.
    D.      Petitioner Cannot Satisfy the Remaining Althen Prongs.
    Petitioner’s obligation under the second and third Althen prongs is to demonstrate a logical
    sequence of cause and effect connecting the particular facts of his case to his medical theory, and
    to show that onset of his injury occurred in a medically appropriate timeframe consistent with his
    theory. Sturdivant v. Sec’y of Health & Human Servs., No. 07-788V, 
    2016 WL 552529
    , at *18
    (Fed. Cl. Spec. Mstr. Jan. 21, 2016) (discussing that Althen prong two requires a fact-based inquiry
    into whether the vaccine in question did cause the particular injury); Bazan, 
    539 F.3d at 1352
    (discussing standards for prong three). Here, Petitioner failed to establish either prong, for several
    reasons.
    With respect to the “did cause” prong, I have found that the overall record does not support
    the conclusion that the flu vaccine was causal of Petitioner’s post-vaccination condition. Dr.
    Leist’s reading of the relevant medical records on this point was persuasive; that record better
    supports the conclusion that Mr. Hayward’s thromboembolic condition existed at the time of his
    vaccination, even if he had not yet experienced overt clinical symptoms. There is no evidence of
    the production of inflammatory cytokines either that would corroborate Petitioner’s theory – and
    although Petitioner was admittedly never tested for such markers, even if he had been their
    presence could equally have been attributed to the prior strokes Petitioner had recently
    24
    experienced. In addition, none of Petitioner’s treaters proposed his vaccination had any
    relationship to his stroke, and the medical record otherwise does not establish any immediate
    reaction to the vaccine, or evidence that Petitioner was experiencing a biologic reaction to the
    vaccine.
    Regarding the third Althen prong, Petitioner hangs his hat on circular reasoning, concluding
    that the close timing of his injury (within 12 hours) to receipt of the flu vaccine establishes a
    reasonable timeframe. In fact the opposite is true - as the literature offered by Respondent (and
    discussed by Dr. Leist) established, it would likely take longer than half a day to generate sufficient
    cytokines to be pathologic in the manner proposed by Petitioner’s theory. Dr. Leist also presented
    reliable medical literature establishing that even patients who are at-risk for CVA and exposed to
    agents that increase the production of cytokines do not experience a CVA event so close in time
    to their receipt of such treatment. See generally, Naina; First Leist Rep. at 6. This, plus the broader
    deficiencies with Petitioner’s theory (which did not otherwise establish that the flu vaccine could
    either directly cause or exacerbate strokes), renders me unable to find that the timing at issue in
    this case of the alleged vaccine-induced stroke has been shown to be medically acceptable.
    CONCLUSION
    The record does not support Mr. Hayward’s contention that the flu vaccine caused his
    CVA/stroke, that Petitioner’s condition was significantly aggravated by the vaccine, or that the
    vaccine caused his injuries in a medically acceptable timeframe. Petitioner has not established
    entitlement to a damages award, and therefore I must DISMISS his claim.
    In the absence of a timely-filed motion for review (see Appendix B to the Rules of the
    Court), the Clerk shall enter judgment in accordance with this decision.15
    IT IS SO ORDERED.
    /s/ Brian H. Corcoran
    Brian H. Corcoran
    Special Master
    15
    Pursuant to Vaccine Rule 11(a), the parties may expedite entry of judgment by filing a joint notice renouncing their
    right to seek review.
    25