Blackburn v. Secretary of Health and Human Services ( 2015 )


Menu:
  •                           In the United States Court of Federal Claims
    OFFICE OF SPECIAL MASTERS
    No. 10-410V
    (To be Published)
    *************************
    *                                               Special Master Corcoran
    SHEELA BLACKBURN,          *
    *                                               Filed: January 9, 2015
    Petitioner, *
    *
    v.               *
    *                                               Entitlement Ruling; Human Papillomavirus
    SECRETARY OF HEALTH        *                                               (“HPV”) Vaccine; Guillain-Barré
    AND HUMAN SERVICES,        *                                               Syndrome (“GBS”); Chronic Inflammatory
    *                                               Demyelinating Polyneuropathy (“CIDP”);
    Respondent. *                                               Molecular Mimicry; Homology; Onset
    *
    *************************
    Isaiah R. Kalinowski, Maglio, Christopher & Toale, Washington, DC, for Petitioner.
    Ann D. Martin, U.S. Dep’t of Justice, Washington, DC, for Respondent.
    ENTITLEMENT DECISION1
    On June 30, 2010, Sheela Blackburn2 filed a petition seeking compensation under the
    National Vaccine Injury Compensation Program3 (the “Vaccine Program”) alleging that she
    suffered a variant of Guillain-Barré syndrome (“GBS”) caused by her receipt of the Human
    1
    Because this decision contains a reasoned explanation for my action in this case, it will be posted on the United
    States Court of Federal Claims’ website, in accordance with the E-Government Act of 2002, Pub. L. No. 107-347, §
    205, 
    116 Stat. 2899
    , 2913 (codified as amended at 
    44 U.S.C. § 3501
     note (2006)). 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. To do so, Vaccine Rule 18(b) permit each party 14 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 decision will be available to the
    public. Id.
    2
    The case was originally titled Sheela Roten v. Sec’y of Health & Human Servs., but the caption was changed by
    Order dated March 1, 2013 (ECF No. 50) after Petitioner changed her legal name.
    3
    The National Vaccine Injury Compensation Program comprises 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.A. ' 300aa-10 – 34 (2006))
    [hereinafter “Vaccine Act” or “the Act”]. Individual sections references hereafter will be to ' 300aa of the Act.
    Papillomavirus (“HPV”) vaccine on July 23, 2009. Petition (ECF No. 1) at 1. An entitlement
    hearing in this matter was conducted in Washington, DC on March 25 - 26, 2014.
    The case presents two intertwined questions: (a) whether Ms. Blackburn suffered from
    GBS, and (b) whether Ms. Blackburn’s illness began before she received the HPV vaccine. After
    hearing the testifying witnesses and reviewing the parties’ various pre- and post-trial
    submissions, and based on a review of the entire record as required by the Vaccine Act (§ 300aa-
    13(a)(1)), I hereby rule in favor of Respondent, for the reasons set forth below.
    I.     Factual Background and Medical History
    A.      Petitioner’s Pre-Vaccination Medical History
    Before Ms. Blackburn ever received the vaccination that is the basis for her claim, she
    had visited healthcare professionals complaining of symptoms similar to those she alleges
    resulted from the vaccination, although their etiology was at that time unclear.
    On October 24, 2008, Ms. Blackburn visited a chiropractor, Mark Snow, and complained
    of left hip and shoulder pain. Pet’r’s Ex. 4 at 2-3. In the course of that examination, she reported
    constant numbness in her feet and frequent numbness in her hands. Id. Thereafter, on November
    6, 2008, Ms. Blackburn was seen at the Exodus Health Care Magna Clinic in Magna, Utah,
    where she reported numbness in her feet over the prior four months, plus more recent numbness
    and tingling in her hands. Pet’r’s Ex. 2 at 15-16. Ms. Blackburn also indicated that she was
    experiencing nerve pain both in her left shoulder and hip area, which she claimed to be an
    ongoing problem. Id. at 15. She received a diagnosis of a “pinched nerve in lower back, neck,
    and hip arthritis,” but unspecified polyarthritis and neuralgia/neuritis were listed as other
    possible sources of her symptoms. Id. at 15-16.
    A few days later, on November 13, 2008, Ms. Blackburn went back to the Exodus Clinic
    and was seen by Dr. Jill McBride. Pet’r’s Ex. 2 at 14. The assessment recorded at the time of this
    visit indicated that Ms. Blackburn was believed to be suffering from an unspecified polyarthritis
    as well as neuralgia/neuritis. Id.
    Based on Dr. McBride’s referral, Ms. Blackburn saw Dr. Susan Zimmerman in December
    of 2008 at the Granger Medical Clinic in Salt Lake City for a neurologic consultation. Pet’r’s Ex.
    8 at 18. At that time, Petitioner again represented she had been experiencing shoulder pain and
    paresthesias for the past four months. Id. Ms. Blackburn’s neurology examination was significant
    for revealing “mild sensory loss and left-side hyperalgesia,” although she presented normal
    reflex responses. Id. at 19. Because the precise cause of Ms. Blackburn’s symptoms remained
    unclear, Dr. Zimmerman made a number of treatment and diagnostic recommendations. In
    particular, Dr. Zimmerman ordered magnetic resonance imaging (“MRI”) of Petitioner’s brain
    2
    and cervical spine “[t]o help exclude problems such as demyelination, cervical cord
    compression, tumor or other focal lesions,” and raised the possibility of “proceed[ing] to a
    lumbar puncture or nerve conduction studies to look for other central or peripheral causes of
    numbness as well.” Id. The MRIs ordered by Dr. Zimmerman were performed on December 31,
    2008. Id. at 10-12. The brain scan results were essentially normal, and the MRI of Petitioner’s
    cervical spine revealed “minimal to mild degenerative changes.” Id.
    Less than a month later, on January 14, 2009, Ms. Blackburn had a follow-up visit with
    Dr. Zimmerman. Pet’r’s Ex. 8 at 7-8. Petitioner indicated that she was still experiencing
    significant right shoulder pain as well as some numbness and pain down both legs (which she
    attributed to sciatica) plus foot numbness. Id. at 7. Upon physical examination, Dr. Zimmerman
    found that Petitioner had “very mild distal sensory loss.” Id. He recommended physical therapy
    to relieve some of the pain that Petitioner was experiencing. Id. Additionally, Dr. Zimmerman
    informed Petitioner about the potential of undergoing nerve conduction studies in an attempt to
    identify the source of her pain, but Petitioner decided to wait and see if her symptoms improved
    with physical therapy. Id. Accordingly, such testing was never performed until well after Ms.
    Blackburn’s vaccination.
    B.      July 2009 HPV Vaccination and Subsequent Medical History
    Petitioner received an injection of the Gardasil vaccination in her left deltoid on July 23,
    2009, during a comprehensive medical examination at Exodus Health Care Clinic performed by
    Cathy Baxter, APRN. Pet’r’s Ex. 6 at 1. The past medical history section of the records from that
    visit, reported that Ms. Blackburn previously experienced an unspecified polyarthritis as well as
    neuralgia/neuritis. Pet’r’s Ex. 2 at 11. Ms. Blackburn also reported “in [the] past couple of weeks
    having tingling in legs and feet,” although her reflexes were tested and recorded to be within
    normal limits, as well as her cranial muscle responses. Id. at 12.
    On August 7, 2009, Ms. Blackburn again presented to Exodus where she was seen by
    Nurse Baxter. Pet’r’s Ex. 2 at 9. Petitioner indicated that she had been fine until just recently but
    was now experiencing “worsening tingling in legs and weakness,” with her legs feeling heavy as
    well. Id. (emphasis added). As the contemporaneous medical records note, there had been “no
    findings on all workup last year” as to the source of her condition, although the records again
    referenced unspecified polyarthritis as well as neuralgia/neuritis. Id. Ms. Blackburn obtained a
    note for light duty at work due to her weakness and discomfort. Id. at 10.
    A few days later, on August 11, 2009, Petitioner returned to Dr. Zimmerman (the
    neurologist she had seen at the beginning of the year) for a “semi-urgent follow-up” regarding
    her ongoing numbness and pain. Pet’r’s Ex. 8 at 4-5. Petitioner reported that “[s]he was doing
    reasonably well until [three] weeks ago,” but that she was now experiencing “complete
    numbness from her knees down bilaterally” as well as back pain and muscle spasms and some
    less severe right shoulder pain. Id. at 4. Notes from the neurological exam performed by Dr.
    3
    Zimmerman indicate that the exam was “notable for areflexia[4] and ankle dorsiflexion weakness
    bilaterally.” Id. Dr. Zimmerman also stated that “no cause of her pain has yet clearly been
    identified,” but that the onset of Ms. Blackburn’s symptoms occurred in the “context of increased
    stress” given that Petitioner worked two jobs. Id.5 No connection between Ms. Blackburn’s July
    23rd vaccination and her symptoms was made at this time.
    In order to diagnose the cause of Ms. Blackburn’s symptoms, Dr. Zimmerman
    recommended a MRI of the lumbar spine plus a lumbar puncture (in light of her demonstrated
    areflexia) to “look for the cyto-albuminologic dissociation that can be seen in Guillain-Barré
    syndrome,” but Petitioner refused to undergo the latter. Pet’r’s Ex. 8 at 4-5. The MRI did not
    reveal the presence of any abnormalities. Id. at 2-3.
    Ms. Blackburn thereafter went back to her chiropractor, Mark Snow, on August 17, 2009,
    complaining of continued pain in her left shoulder as well as the previously-reported numbness
    in her hands and feet. Pet’r’s Ex. 4 at 4. Deep tendon reflex (“DTR”) testing performed during
    the visit revealed normal reflexes in her upper body limbs, but areflexia in her knees and right
    ankle. Id. at 5. Cranial nerve testing, however, revealed no abnormalities, and the record from
    this visit specifically indicated that Ms. Blackburn was “able to perform the normal range of
    facial movements, no asymmetry or other abnormalities were noted.” Id.
    Ms. Blackburn saw Mark Snow again two days later, at which time she underwent a
    nerve conduction velocity study, the results of which were abnormal. Pet’r’s Ex. 4 at 7. Results
    from that study and an electromyography (“EMG”)6 were reviewed by Robert A. Sellin, PT,
    DSc, ECS, a board certified electromyographer. Id. at 12. Those nerves tested had normal
    amplitudes, latencies, and nerve conduction velocities, but there was no measurable sensory
    response from any of the sensory nerves tested; the left median motor distal latency was severely
    prolonged and the distal nerve conduction velocity was markedly slowed; the left ulnar motor
    distal latency was severely prolonged and the segmental nerve conduction velocities were
    markedly slowed; bilateral fibular (peroneal) motor responses were not obtainable; bilateral tibial
    motor evoked responses were of markedly diminished amplitude and exhibited severe temporal
    dispersion; bilateral common fibular (peroneal) and tibial motor F-waves were not obtainable;
    and the left median and ulnar motor F-waves were severely prolonged. Id. The remarks included
    4
    Areflexia is defined as the absence of reflexes. Dorland’s Illustrated Medical Dictionary (32d ed. 2012) at 130
    [hereinafter “Dorland’s”].
    5
    The medical records from this visit with Dr. Zimmerman also reflect that Petitioner reported that “[five] weeks ago
    [i.e. some time in July 2009] she had symptoms similar to a friend, who was diagnosed with strep throat,’ although
    “[s]he did not seek medical attention at that time.” Pet’r’s Ex. 8 at 4.
    6
    Electromyography (“EMG”) is “an electrodiagnostic technique for recording the extracellular activity (action
    potentials and evoked potentials) of skeletal muscles at rest, during voluntary contractions, and during electrical
    stimulation.” Dorland’s at 602.
    4
    with the testing results indicated that “[t]hese electrophysiologic findings combined with her
    history are strongly suggestive of some form of acute inflammatory demyelinating
    polyradiuloneuropathic process (AIDP)[7] such as Guillain-Barre syndrome).” Id. at 8. The
    remarks also indicated that “I believe it is important to note that the patients symptoms were very
    mild [six] weeks ago and she received immunization about [five] weeks ago and then noticed her
    increasing symptoms. Id. at 9 (emphasis added). The EMG results revealed that “[a]ll muscles
    tested exhibited normal insertional activity, electrical silence at rest, and had normal motor unit
    configuration and recruitment, except: There was reduced interference patterns in all muscles
    tested except the left deltoid.” Id. at 9-10.
    On August 24, 2009, Ms. Blackburn went to the University Health Care Emergency
    Department at the University Health Care Hospitals and Clinics in Salt Lake City, Utah
    complaining of three and a half weeks of progressive ascending weakness and numbness as well
    as back pain, and noting that her condition had occurred after receipt of the Gardasil Vaccine.
    Pet’r’s Ex. 3 at 19. She specifically reported that she last felt well on July 4th when she became
    ill with flu-like symptoms, and then later that month received the Gardasil vaccination. Id.
    During this visit, Ms. Blackburn noted that for the first two weeks her symptoms were mild and
    that she had seen Dr. Zimmerman, but her symptoms had progressed to the point where she was
    having difficulty walking. Id. The contemporaneous medical records from this visit included
    GBS and multiple sclerosis (“MS”) as potential differential diagnoses. Id. at 42.
    The next day Ms. Blackburn saw Dr. Jeffrey C. Wagner, a neurologist. Pet’r’s Ex. 12 at
    35-36. She informed Dr. Wagner that she had been using a walker since her visit to Dr.
    Zimmerman earlier in August, and that she was experiencing more tingling, numbness, and
    weakness in her hands and arms. Id. at 35. Petitioner again reported having experienced “strep or
    flu-like symptoms at the beginning of July” with “associated neck stiffness,” but she noted that
    these symptoms had improved and “she was feeling back to her usual state of health by the end
    of July when she presented for a general annual physical exam” and “received the Gardasil
    vaccination.” Id. at 35-36. After examination of Petitioner and review of her history, Dr. Wagner
    stated that Ms. Blackburn appeared to have a “history on exam consistent with Guillain Barré
    syndrome.” Id. at 38.
    Based on this GBS diagnosis, Dr. Wagner recommended that Ms. Blackburn be admitted
    to the Inpatient Neurology Service at the University Hospital for a course of intravenous
    immunoglobulin (“IVIG”).8 Pet’r’s Ex. 12 at 38-39; Pet’r’s Ex. 7 at 25, 29, 30. Dr. Wagner also
    7
    AIDP refers to acute inflammatory demyelinating polyradiculoneuropathy, a common GBS variant. P. Dyck &
    P.K. Thomas, 2 Peripheral Neuropathy 2199 (4th ed. 2005) [hereinafter “Dyck & Thomas”].
    8
    IVIG treatments are used with patients suffering from neuropathies like GBS and other illnesses believed to have
    an autoimmune character, and help patients maintain sufficient antibody levels. Dyck & Thomas at 642-43. The
    exact mechanism of action for IVIG in individuals with GBS is unknown, but the American Academy of Neurology
    Practice Parameter Group recommends “consideration of IVIg for patients within [two] weeks and probably within
    5
    ordered an EMG, which was performed on August 26, 2009. Pet’r’s Ex. 3 at 45. Dr. Wagner’s
    written interpretation of these EMG results stated that “[t]here is electrodiagnostic evidence of a
    severe demyelinating peripheral neuropathy consistent with the presumed diagnosis of Guillain
    Barré Syndrome (acute inflammatory demyelinating polyradiculoneuropathy, AIDP).” Pet’r’s
    Ex. 5 at 124. Dr. Wagner’s notes go on to indicate that “[t]he low compound muscle action
    potential amplitude in the median motor response implies significant axonal damages as to the
    fibrillations and positive waves in anterior tibialis muscle.” Id.
    During her hospitalization, Petitioner “received 2 g/kg of IVIG treatment over three days
    and developed nausea and vomiting, as well as anemia, which was diagnosed as hemolytic
    anemia” attributed to the IVIG treatment (not an uncommon occurrence).9 Pet’r’s Ex. 7 at 6-7.
    Despite such treatment complications, Ms. Blackburn completed her course of IVIG on August
    28, 2009, showing “dramatic improvement in her symptoms” and was therefore discharged from
    inpatient neurology care at the University Hospital. Id. at 23, 25, 33. Dr. Wagner indicated upon
    discharge that Ms. Blackburn was to undergo physical rehabilitation for further treatment, and
    cautioned that “[g]iven the patient’s reaction to Gardasil vaccine, she is not to complete the 3-
    step series and is also not to receive further vaccines given her risk of [GBS].” Id. at 24.
    Petitioner was thereupon transferred to Acute Rehabilitation Service at the University of
    Utah for comprehensive treatment, as she was still experiencing difficulty in movement. Pet’r’s
    Ex. 7 at 29-30. Petitioner nevertheless continued to be followed by the hospital’s Neurology
    service. Id. at 19. A few weeks later, on September 5, 2009, Petitioner was discharged from her
    rehabilitation, having “made significant functional gains during her stay,” with discharge
    diagnoses of “(1) [a]cute inflammatory demyelinating polyradiculoneuropathy; (2) [n]europathic
    pain; [and] (3) [h]emolytic anemia secondary to IVIG.” Id. at 18, 20.
    C.             Petitioner’s Ongoing Symptoms and Eventual Change in Diagnosis
    Ms. Blackburn continued to undergo physical and occupational therapy throughout
    September of 2009. See generally Pet’r’s Ex. 1. Despite her general progress and nascent
    recovery, results from a September 18, 2009 EMG study were interpreted by Dr. Wagner as
    abnormal due to “electrodiagnostic evidence of a primary demyelinating neuropathy with
    secondary axonal damage” as well as “evidence of early reinnervation.”10 Pet’r’s Ex. 5 at 363.
    [four] weeks of the onset of symptoms” even though “[a]ccording to a Cochrane systematic review, there are no
    adequate trials comparing IVIg to placebo” in patients with GBS. Id.
    9
    Petitioner’s medical records contain the observation that “[t]here are multiple case reports describing hemolysis in
    the setting of high-dose IVIG treatment.” Pet’r’s Ex. 7 at 27.
    10
    Reinnervation is defined as the restoration, by regrowth or by grafting, of nerve supply to a part of the body from
    which it has been lost. Dyck & Thomas at 1421-22.
    6
    As of early October, Ms. Blackburn appeared to be recovering and reported a
    diminishment of her symptoms. Pet’r’s Ex. 3 at 61. By October 22, 2009, however, when Ms.
    Blackburn was seen by Katarina Waters, PNP,11 she had begun to experience increased bilateral
    numbness below her knees, weakness in bilateral lower extremities, and was also having trouble
    walking, making Petitioner concerned that she was suffering a relapse. Pet’r’s Ex. 3 at 58. A
    physical examination revealed that her reflexes were (again) absent in both knees and ankles, and
    that she had decreased bilateral sensation from her knees down. Id. at 59. Because a neurologic
    evaluation could not be immediately scheduled, Ms. Blackburn was sent to the emergency room.
    Id. at 60.
    At the hospital emergency department, Ms. Blackburn complained of “worsening
    weakness and numbness the onset of which had been gradual” but which had flared in the prior
    one and a half weeks. Pet’r’s Ex. 3 at 39; Pet’r’s Ex. 7 at 14-15. She reported that she had
    previously spoken to Dr. Rosenbluth about her symptoms and he indicated that she may need
    more IVIG, so she was told to come to the Emergency Department for possible admission.
    Pet’r’s Ex. 7 at 15. A physical examination performed at this time revealed decreased sensation
    to touch of her lower extremities below her knee, no pain sensation of her feet, decreased
    temperature sensation to her bilateral feet, and loss of proprioception of her toes. Pet’r’s Ex. 3 at
    39-40. The doctors who evaluated her, however, did not conclude that inpatient admission for
    IVIG treatment was appropriate despite her symptoms. Pet’r’s Ex. 7 at 16.
    In the following days, Ms. Blackburn continued to experience the recurrence of many of
    the severe symptoms she had just received treatment for in August (i.e., bilateral and ascending
    limb weakness), leading her to see Dr. Jackie J. Whitesell in the Neuromuscular Disease Clinic
    on October 29, 2009. Pet’r’s Ex. 3 at 64-65. A physical examination confirmed the areflexia in
    her arms and legs (as observed at her emergency department visit earlier that month) as well as
    some numbness in her legs. Id. at 66. Dr. Whitesell indicated in her notes that “I feel that this
    likely still represents slowly improving Guillain-Barré which can sometimes have a waxing and
    waning course . . . I feel that an alternative diagnosis of CIPD [chronic inflammatory
    demyelinating polyneuropathy] is less likely.” Id. Dr. Whitesell did not, however, explain why
    she discounted the possibility of CIDP, indicating only her conclusion that based on the
    examination, Petitioner had “AIDP with continued weakness and numbness in her extremities.”
    Id.
    Ms. Blackburn’s symptoms did not dissipate (as had been anticipated when she first
    completed her IVIG treatment in late August 2009) in the months that followed. However, her
    condition did not impel her to visit another doctor again until the spring of 2010 – nine months
    after the vaccination. At that time, on April 22, 2010, Ms. Blackburn presented to Mark B.
    Bromberg, M.D. in the Neuromuscular Clinic at the University of Utah Hospitals and Clinic in
    11
    Medical notes from that visit were electronically signed by Dr. Rosenbluth. Pet’r’s Ex. 3 at 58.
    7
    Salt Lake City, Utah with complaints of limb weakness that had for the past six months
    fluctuated on an almost daily basis. Pet’r’s Ex. 7 at 6-7. Although Petitioner reported that she
    was doing better, she indicated that she had not returned to baseline and was still experiencing
    “aches and pains, with neuropathic pain, as well as muscle spasms.” Id.
    Dr. Bromberg’s notes state that Ms. Blackburn was “here for another evaluation for her
    history of AIDP with a question of if there is a component of chronic involvement or just
    delayed and incomplete recovery.” Pet’r’s Ex. 7 at 8. However, given Petitioner’s history of
    unresolved, waxing-and-waning symptoms, Dr. Bromberg questioned whether the prior AIDP
    diagnosis was in fact correct. Id. As he specifically indicated:
    [h]er overall history does fit a monophasic illness, given the vaccine-related symptoms,
    as well as the lack of true exacerbation throughout her course in the past couple months.
    However, she still has significant disability from her arm and leg weakness, as well as
    pain. At this point, we would like to give her a trial of prednisone,12 given that she has
    had more side effects with IVIG in the past. [] We would expect significant and
    noticeable clinical benefit if this were CIDP and if she does not have significant
    response, then this steers us towards this being a monophasic AIDP with prominent
    axonal injury and delayed and perhaps incomplete recovery.
    Id. (emphasis added). Accordingly, Ms. Blackburn was prescribed prednisone and instructed to
    come in for a follow-up appointment within five to six weeks. Id. at 8-9.
    By the time of Ms. Blackburn’s follow-up visit on June 24, 2010, Dr. Bromberg was able
    to observe that since beginning prednisone two months prior, Petitioner exhibited “subjective
    and objective improvement.” Pet’r’s Ex. 7 at 2-3. He thus indicated in his notes that Petitioner
    “was thought initially to have AIDP. However, given her lack of complete improvement and now
    improvement on prednisone, this suggests that she has rather CIDP as explanation of her
    symptoms.” Id. at 4 (emphasis added).
    D.             Ms. Blackburn’s More Recent Treatment History
    Since Ms. Blackburn’s diagnosis was changed to CIDP, she has (consistent with that
    diagnosis) continued to experience symptoms on a waxing and waning basis, and has thus been
    seen regularly by a number of providers to follow-up on and attempt to manage her symptoms.
    But nothing in the subsequent record contradicts the consensus among Ms. Blackburn’s treating
    physicians that the initial diagnosis of AIDP had been in error. See, e.g., Pet’r’s Ex. 12 at 6 (Dr.
    Bromberg’s notes from her February 2011 visit). Consistent with that, any initial efforts to take
    Ms. Blackburn off prednisone lead to a recurrence of her symptoms such as numbness in her
    upper and lower extremities. Id.
    12
    Prednisone is “a synthetic glucocorticoid derived from cortisone, administered orally as an anti-inflammatory and
    immunosuppressant in a wide variety of disorders.” Dorland’s at 1509.
    8
    In a May 2011 follow-up visit with Dr. Bromberg, it was noted that Petitioner was
    continuing to take prednisone and was doing well since her last visit other than experiencing
    some mild paresthesias in her limbs and fatigue – symptoms that Dr. Bromberg characterized as
    natural fluctuations commonly experienced by CIDP patients. Pet’r’s Ex. 11 at 2-3. Petitioner
    thereafter continued to follow-up with Dr. Bromberg and other treatment providers to gauge her
    progress, and also to evaluate whether IVIG could ever be tried again in the event of another
    relapse (leading to a determination that future IVIG treatment was not contraindicated). Pet’r’s
    Ex. 29 at 79-80, 85-88. Ms. Blackburn saw Dr. Bromberg again in the spring of 2012 to address
    the treatment management of her CIDP, and he concluded that her illness appeared to be in
    remission despite the tapering off of her steroid treatment. Id. at 77-78. The remaining medical
    records filed in this case indicate that Petitioner has not subsequently experienced a severe
    recurrence of her CIDP and has not required ongoing prednisone treatment.13
    II.           Expert Testimony
    Three experts testified at hearing: one for Petitioner and two for Respondent. The
    qualifications and testimony of each side’s respective experts are summarized below.
    A.             Petitioner’s Expert – Dr. Steinman
    Lawrence Steinman, M.D. is a professor in Stanford University’s Departments of
    Neurology, Pediatrics, and Genetics, and the chair of Stanford’s Immunology Program. Pet’r’s
    Ex. 17 (Dr. Steinman’s curriculum vitae). He has been elected to the Institute of Medicine
    (“IOM”) and has published more than 400 articles, including articles related to his research on
    autoimmune disease and molecular mimicry. Id. Dr. Steinman’s primary focus is on MS, but
    during the thirty-two years that he has been a board-certified neurologist he has treated
    approximately 400 patients with GBS (although, unlike Ms. Blackburn, approximately sixty-five
    percent of these patients that he has treated were children). Tr. at 144-46. Of those 400 patients,
    Dr. Steinman indicated that approximately twenty-five percent could be characterized as having
    CIDP. Id. at 146.
    13
    On June 18, 2012, Petitioner presented for her six-month follow-up appointment. Pet’r’s Ex. 29 at 7. Even without
    steroid treatment at that time, she generally appeared to be doing well, although she complained of some lingering
    upper and lower body bilateral weakness as well as occasional fevers the cause of which could not be identified by
    tests. Id. On November 26, 2012, Petitioner was again seen for a follow-up appointment and reported that she was
    doing well. Id. at 19. Thereafter, on April 18, 2013, Petitioner was seen for a follow-up appointment, and it was
    noted that she was “pregnant for 9 weeks now” and reported that she was doing well – although because she had
    decreased her doses of medication during her pregnancy, she was occasionally experiencing some of the old
    symptoms. Id. at 48-49.
    9
    Dr. Steinman admitted that due to his focus on research, he has seen considerably fewer
    patients in the last five years than he saw earlier in his career, but he still sees patients (including
    approximately eighty patients as of March 2014, which he estimated to be less than the number
    of patients that he saw in 2013). Tr. at 144-45. During the last five years, Dr. Steinman has only
    seen patients approximately one month out of the year when he serves as an inpatient attending
    physician, and during this time he has been called to diagnose an individual with GBS or CIDP
    no more than about sixteen or seventeen times (including once in 2014 as of March of that year).
    Id. at 147. Additionally, Dr. Steinman has not conducted nerve conduction studies or interpreted
    the results from such studies since his initial training. Id. at 149. Moreover, Dr. Steinman
    acknowledged that no patients with CIDP have been referred to him for management of their
    long-term care in the last five years. Id. at 147.
    Dr. Steinman offered an opinion on two topics: (1) a theory by which he proposed the
    HPV vaccine Ms. Blackburn received could have caused an autoimmune response leading to her
    purported GBS, and (2) whether, based upon his review of Ms. Blackburn’s medical records, he
    believed her illness was AIDP or CIDP.
    1. Dr. Steinman’s Molecular Mimicry Theory – Dr. Steinman proposed the theory
    of molecular mimicry to explain how the HPV vaccine could cause GBS (including the AIDP
    variant of GBS). Molecular mimicry has been defined to be a “sequence and/or conformational
    homology between an exogenous agent (foreign antigen) and self-antigen leading to the
    development of tissue damage and clinical disease from antibodies and T cells directed initially
    against the exogenous agent that also react against self-antigen.” Institute of Medicine, Adverse
    Effects of Vaccines: Evidence and Causality at 70 (Stratton K. et al., eds. 2011) [hereinafter
    “Adverse Effects of Vaccines”]; see also Tr. at 21-24; Steinman L., Autoimmune Disease, 269
    Scientific America 106-14 (Sept. 1993) (Pet’r’s Ex. 19). As Dr. Steinman explained in his
    testimony, invading microbes mimic the structure of host proteins. Tr. at 21. Because of these
    shared structures, when certain hosts develop an immune response to the invading microbes,
    their immune systems confuse self with foreign proteins, attacking both. Id. at 22-23. For
    molecular mimicry to occur, sufficient homology (a term Dr. Steinman defined broadly as
    “similarity” (Id. at 36)) must exist between self and foreign antigens. Id. at 35, 38, 192.14
    All forms of GBS, Dr. Steinman testified, are autoimmune diseases occurring after the
    body mounts an immune response to a foreign agent that accidently targets the body’s own nerve
    tissue – through molecular mimicry. Tr. at 19. One of the most well-known examples of
    molecular mimicry as the mechanism for GBS, he stated, involves a structure shared between a
    14
    Though homology is necessary to trigger molecular mimicry, Dr. Steinman conceded that the existence of
    homology alone does not lead automatically to the conclusion that molecular mimicry has or will occur. Tr. at 56-
    57. Indeed, homology occurs frequently without any clinical effect. Adverse Effects of Vaccines at 71. Most cross-
    reactivity does not even lead to autoimmunity. Tr. at 161-62.
    10
    bacterium called Campylobacter jejuni and gangliosides, sugar structures found on the surface of
    myelin (which is present in large quantities in human peripheral nerve tissue). Id. at 25. Thus, an
    antecedent Campylobacter jejuni infection can, through molecular mimicry, lead to a particular
    GBS variant called acute motor axonal neuropathy (“AMAN”).15 Id. Dr. Steinman opined that it
    is medically accepted (while not fully understood) that certain vaccines can also cause GBS,16
    initiating an autoimmune process the same way another microbe (like the Campylobacter
    bacterium) might. Id. at 35. The components of the wild viruses contained in many vaccines
    actually share molecular homologies with myelin structures present in the human body, and thus
    could produce the same reaction as a wild virus alone. Id.
    Dr. Steinman proposed a specific means by which molecular mimicry occurs within an
    autoimmune reaction between the HPV vaccine and the body. Dr. Steinman contended that the
    HPV virus (portions of which the Gardasil vaccine contains17) shares “molecular similarities”
    with certain amino acid peptides making up myelin basic protein (“MBP”), which he defined as
    “the most common protein in central and peripheral nervous system myelin.” Tr. at 29, 39-40.
    After receipt of the HPV vaccine, in the course of the human body’s adaptive immune response
    the host’s immune system would be “tricked” into attacking MBP, the putative target antigen of
    the autoimmune response. Id. at 51, 162, 192-93.
    Dr. Steinman’s conception of homology was specifically based on structural similarities
    between components of the HPV vaccine and host tissues, and he applied that paradigm to
    explain how MBP would be putatively attacked. Tr. at 36, 38. In his testimony, he repeatedly
    employed the metaphor of a “catcher’s mitt” (a groove formed on the host tissues by the human
    leukocyte antigen (“HLA”))18 holding a peptide from the vaccine which would then be presented
    to a host T cell.19 Id. at 18-22, 156-57. The peptide would “fit” into the catcher’s mitt due to its
    15
    AMAN is an autoimmune neuropathy that principally targets motor nerve axons. Dyck & Thomas at 575; Tr. at
    16. Because there is a much higher incidence of Campylobacter jejuni infection in China than the United States,
    AMAN is rarer here. Tr. at 34-35.
    16
    Dr. Steinman specifically cited the epidemiologic evidence derived from the 1976 swine flu outbreak (as outlined
    in the Schonberger article (Schonberger, L.B. et al., Guillain-Barré syndrome Following Vaccination in the National
    Influenza Immunization Program, United States, 1976-1977, 110(2) Am. J. Epidemiol. 105–23 (1979) (Pet’r’s Ex.
    25) and the Langmuir article (Langmuir, A.D. et al., An Epidemiological and Clinical Evaluation of Guillain Barre
    Syndrome Reported in Association with the Administration of the Swine Influenza Vaccine, 119 Am. J. Epidemiol.
    841-79 (1984) (Pet’r’s Ex. 26)) to support this proposition. Pet’r’s Ex. 19 at 13.
    17
    Gardasil is a recombinant (as opposed to live virus) quadrivalent vaccine prepared from virus-like particles of the
    major capside (L1) protein of HPV Types 6, 11, 16, and 18. Centers for Disease Control and Prevention,
    Quadrivalent Human Papillomavirus Vaccine: Recommendations of the Advisory Committee on Immunization
    Practices (ACIP), 56(RR-2) MMWR 8 (2007) (Pet’r’s Ex. 38 at 3, 10-11); Tr. at 40-42.
    18
    HLA or “human leukocyte antigens” are “histocompatibility antigens governed by genes of the HLA complex (the
    human major histocompatibility complex [MHC]).” Dorland’s at 105.
    19
    T cells are lymphocytes carrying their own unique receptors, some of which recognize the foreign peptide, while
    others recognize the self MHC molecule. Dyck & Thomas at 560-61.
    11
    structural homology with the host protein. Id. at 21-22. It would thereupon give instructions to
    the T cell, which would in turn migrate to MBP on the host’s peripheral nerves and attack,
    causing the demyelination that characterizes GBS. Id. at 17, 155-57, 160-62.
    Dr. Steinman contended that the molecular mimicry process by which MBP was attacked
    could involve T cells, antibodies produced from B cells, or both, with neither being predominant.
    Tr. at 17-18, 24, 155, 161.20 However, although T cells and B cells recognize similar antigens,
    they play different roles in the adaptive immune system; T cells can only recognize structures
    that are bound to the HLA, while antibodies are not so constrained. Id. at 17, 24-25. Dr.
    Steinman’s theory ultimately relied on T cells as playing the primary role in the destruction of
    myelin. Id. at 156-58.
    In support of his assertion that MBP was the target antigen for the molecular mimicry
    process he outlined, Dr. Steinman relied upon the Cornblath study (David R. Cornblath et al.,
    Immunoreactive Myelin Basic Protein in Cerebrospinal Fluid of Patients with Peripheral
    Neuropathies, 20 Annals of Neurol. 370 (1986) (Pet’r Ex. 32)). Tr. at 162. The Cornblath study
    found increased MBP in the spinal fluid of patients with GBS, although it did not find that MBP
    was the target antigen in GBS. Pet’r’s Ex. 32 at 3741. He also relied heavily on an article – Kai
    W. Wucherpfennig et al., Recognition of the Immunodominant Myelin Basic Protein Peptide by
    Autoantibodies and HLA-DR2-Restricted T Cell Clones from Multiple Sclerosis Patients, 100 J.
    Clinical Investigation 1114 (1997) (Pet’r’s Ex. 18) [hereinafter “Wucherpfennig”] – which
    studied cross-reactivity between MBP peptides, on the one hand, and antibodies and T cells, on
    the other, in multiple sclerosis patients. Id. at 28-29, 37.
    Dr. Steinman next attempted to identify the precise homology involved in the purported
    cross-reaction between an epitope21 of MBP and the components of the HPV vaccine. Tr. at 48,
    55-56, 155. Relying on two laboratory studies in which an autoimmune disease (experimental
    autoimmune encephalomyelitis (“EAE”))22 has been induced in mice using peptides from HPV
    40, 32, or the HPV L2 protein23, Dr. Steinman specifically identified HFFKN24 as the critical
    20
    Indeed, not only did Dr. Steinman not substantially distinguish the structural requirements for T cell and B cell
    mimicry, but at some points he conflated the two despite the differences in the way each functions. See Tr. at 17, 46.
    21
    An epitope is the “antigenic determinant.” Dorland’s at 637. “[O]nly the portion of the protein or polysaccharide
    molecule known as the antigenic determinant (q.v.) combines with antibody or specific receptor on a lymphocyte.”
    Id. at 103.
    22
    EAE is an experimental model for MS. Steinman, L., Autoimmune Disease, 269 Scientific American 109 (1993)
    (Pet’r’s Ex. 19).
    23
    See Ruiz P.J. et al., Microbial Epitopes Act as Altered Peptide Ligands to Prevent EAE, 189 J. of Experimental
    Medicine 1275-84 (1999) (Pet’r’s Ex. 21) [hereinafter “Ruiz”]; Ufret-Vicenty et al., In Vivo Survival of Antigen
    Specific T Cells that Induce EAE, 188 J. of Experimental Medicine 1725-38 (1998) (Pet’r’s Ex. 23) [hereinafter
    “Ufret-Vicenty”].
    12
    sequence sharing homology with these HPV strains. Id. at 55-57, 168. Within this sequence,
    FKN is the “core motif” for MBP mimicry, but (based on Dr. Steinman’s view of the structural
    character of homology) an FK or FKN sequence would be sufficient for the cross-reactive
    process to occur. Id. at 48, 168, 192-93; see also Pet’r’s Mem. at 6.
    As Dr. Steinman admitted on the witness stand, however, the homology analysis set forth
    in his written expert report was premised upon an error.25 Tr. at 47. Dr. Steinman’s report had
    described homology between MBP and the L2 protein of HPV (strains 7, 13, and 40). Id. at 48-
    49; Pet’r’s Ex. 16 at 8. However, Gardasil is manufactured from the L1 protein of HPV (strains
    6, 11, 16, and 18) – not the L2. Pet’r’s Ex. 38 at 8. The sequences he described are thus not
    included as components of the Gardasil HPV vaccine, and therefore (as Dr. Steinman admitted)
    his initial analysis was “not germane” to the actual formulation of the relevant HPV vaccine. Tr.
    at 48-49, 135.26
    Dr. Steinman attempted to correct his mistake through his live testimony, supported by
    additional medical literature filed before the March hearing. Tr. at 48-49; Pet’r’s Ex’s 41-44
    (medical literature); Pet’r’s Pre-Hr’g Reply Mem. (ECF No. 60) at 6-10; Pet’r’s Ex. 46 at 1
    (demonstrative exhibit). To do so, he indicated that after he discovered the error, he conducted
    what he termed “an experiment done, if you will, in silico [meaning performed on a computer] at
    my desk with publicly available databases.” Tr. at 47. In effect, he looked up on the Internet the
    published genome sequences relevant to the actual components of the Gardasil vaccine and then
    compared them to the protein sequences found in MBP.
    In so doing, Dr. Steinman determined that the L1 proteins contained in the Gardasil HPV
    vaccine included the amino acid sequences “YKN” and “FK.”27 Tr. at 52. Dr. Steinman then
    asserted that F and Y are “pretty much interchangeable,” due to their shape and spatial position
    in the overall protein sequence, illustrating his point with visual charts representing how the
    24
    “H” refers to the amino acid histidine, “F” refers to phenylalanine, “K” refers to lysine, and “N” refers to
    asparagine. Tr. at 39-44; Pet’r’s Ex. 46 at 1. The amino acids in this sequence may be referred to as H88, F89, F90,
    K91, and N92. Wucherpfennig at 1117.
    25
    Dr. Steinman’s written report was filed in July 2012. ECF No. 36. Respondent pointed out in her January 28, 2014
    pre-hearing memorandum (ECF No. 62), however, that Dr. Steinman had not compared the proteins actually
    contained in the relevant formulation of the HPV vaccine in this case to MBP. Because the hearing was held in late
    March of 2014, Petitioner had ample forewarning of the need to respond to this criticism of Dr. Steinman’s
    reasoning, and did so during Dr. Steinman’s testimony.
    26
    Dr. Steinman attributed this error to the fact that when he wrote his report, he “stuck to the viruses that we had
    addressed in this paper by Wucherpfennig.” Tr. at 48.
    27
    “Y” refers to the amino acid tyrosine. Tr. at 43.
    13
    sequences appear in three dimensions after magnification. Tr. at 47, 43, 52-54.28 From a
    homology standpoint, both “keys” would still fit the “lock” represented by the MBP peptide
    sequences, thereby inducing an autoimmune response. Accordingly, Dr. Steinman testified that
    he was still able to maintain the opinion that there is sufficient homology between the actual
    HPV vaccine received by Ms. Blackburn and MBP. Id. at 135, 192-93. Indeed – it was his
    opinion that the homology was even stronger than before, because now there were two possible
    sequences – FK and YKN – to provide a basis for molecular mimicry. Id. at 52, 143.
    2. Dr. Steinman’s Diagnostic Opinion – Dr. Steinman also offered an opinion on
    the nature of Ms. Blackburn’s illness based on a review of her treatment history. Dr. Steinman
    challenged the concept that when Ms. Blackburn presented to Dr. Zimmerman between
    December of 2008 and January of 2009, her symptoms were consistent with the expected
    presentation of an individual suffering from CIDP. Tr. at 70, 92-96,123, 130-31. If an individual
    were suffering from CIDP, he reasoned, a treating physician would expect to observe numerous
    abnormalities from their neurologic exam. Id. at 92. However, Dr. Steinman pointed out that
    diagnostic testing, such as her December 2008 MRI, displayed essentially normal results,29 or
    were logically consistent with the physical demands of her job. Id. at 88-89. He also observed
    that she displayed asymmetric pain and no areflexia.30 Id. at 89-92. And the typical patient with
    CIDP, Dr. Steinman opined, would not be able to continue to work two jobs (one in the nursing
    profession and the other in housecleaning) without seeking treatment, yet Ms. Blackburn had
    done so. Id. at 70; 93-94. In the same vein, Dr. Steinman also noted the gap in Ms. Blackburn’s
    medical records from January of 2009 to July of 2009 – a long time, in his view, for an
    individual with CIDP to not seek medical treatment. Id. at 90-92.
    Dr. Steinman further testified that he considered the post-vaccination AIDP diagnosis to
    be especially reliable and improperly revised to CIDP in 2010. Tr. at 74-75, 123. For example,
    Ms. Blackburn’s neurologist, Dr. Zimmerman, first observed areflexia on August 11, 2009, but
    not before. Id. at 95. In Dr. Steinman’s reading of the records, this was a significant presenting
    symptom, and the fact that it was not seen before vaccination was very important. Id. at 96. He
    28
    In support, Petitioner offered a blown-up x-ray diffraction photograph of the relevant portion of MBP in order to
    illustrate precisely where on the HLA “catcher’s mitt” the homologous portion of the HPV vaccine peptide would
    bind by showing the shapes or structure of the relevant peptide sequences. Tr. at 39-40, 42-44 (referencing Pet’r’s
    Ex. 46).
    29
    In addition Ms. Blackburn’s cranial/cerebellar/sensory motor responses and reflexes (as tested in December 2008
    and January 2009) were within normal limits. Tr. at 91-92. Dr. Steinman further observed that Ms. Blackburn had
    normal reflexes with intact sensation, which he opined was not supportive of a diagnosis of ongoing inflammatory
    demyelination. Id. at 87-88.
    30
    Ms. Blackburn was experiencing shooting pain down one leg, which in Dr. Steinman’s view was not consistent
    with an ongoing process of CIDP where pain would normally be symmetrical. Tr. at 89. Nor did he consider the
    physical therapy treatment prescribed for Petitioner at that time normal treatment recommended for a patient with
    CIDP. Id. at 89-90.
    14
    also considered it important that her subsequent lumbar puncture revealed the anticipated
    albumin dissociation that is a clinical hallmark of GBS. Id. at 105. He questioned whether certain
    symptoms that Respondent argues are critical for a GBS diagnosis that were absent (such as
    cranial facial muscle weakness, respiratory weakness, and autonomic instability) were in fact
    critical. Id. at 71. Dr. Steinman deemed particularly significant the abnormal results obtained
    from the EMG performed on September 18, 2009, which revealed secondary axonal damage31 –
    something he considered uncommon in the case of CIDP. Id. at 66, 112-13.32
    Dr. Steinman also stressed those instances in the treating record where Ms. Blackburn’s
    physicians linked the Gardasil vaccination to her GBS. Tr. at 108. He discounted the possibility
    that Ms. Blackburn’s treating physicians had not taken her prior medical history into account in
    so concluding. Id. at 109. He admitted, however, that to some extent his conclusion arose from
    his assumption that in a “teaching hospital” such as where Ms. Blackburn was treated any
    diagnosis could be assumed to have taken into account a patient’s medical history. Id. at 109-
    10.33
    Dr. Steinman explained the waxing and waning quality of Ms. Blackburn’s symptoms
    after her hospitalization as the product of an incomplete recovery from her initially acute GBS.
    He attributed some of her relapse (which he admitted was “pretty big” (Tr. at 116)) to her having
    received an incomplete series of IVIG treatments due to the hemolytic anemia she developed. Id.
    at 115. This new phase of her disease thus did not negate the AIDP diagnosis, as recurrence is
    not unknown to AIDP patients. Id. at 115-16, 119. Dr. Steinman also emphasized Ms.
    Blackburn’s neurology consult with Dr. Whitesell (who rejected a CIDP diagnosis), and the
    subsequent follow-up EMG and nerve conduction studies, the results of which confirmed
    Petitioner’s recovery (showing reinnervation). Id. at 118-120. Had Ms. Blackburn been suffering
    31
    As Dr. Steinman explained, secondary axonal damage refers to the fact that after the overlying myelin sheath gets
    damaged, the axon within can also become damaged from the consequences of the initial process. Tr. at 112. He
    noted that the AMAN form of GBS is more commonly associated with secondary axonal damage, but distinguished
    Ms. Blackburn’s case by observing that motor and sensory axons were involved (which would not be true for
    AMAN). Id. at 112-13.
    32
    In support of this part of his opinion, Dr. Steinman referenced an article (L. Ruts, M.D. et al., Distinguishing
    Acute-Onset CIDP From Fluctuating Guillain-Barré Syndrome, 74 Neurol. 1680-86 (2010) (Resp’t’s Ex. H)) citing
    a study of GBS and CIDP which found signs of axonal damage were “rare in acute onset CIDP group, while more
    than half of the patients in the GBS treatment-related fluctuations group show signs of axonal damage in the acute
    phase.” Tr. at 66.
    33
    Dr. Steinman testified that in his experience, a teaching hospital (such as the University of Utah where Ms.
    Blackburn received care) is typically staffed with extremely bright interns, residents, and faculty members who are
    challenging every diagnosis. Tr. at 74. Accordingly, Dr. Steinman opined that “for the doctors and professors at a
    major university teaching hospital to have made the diagnosis of acute inflammatory demyelinating polyneuropathy
    based on clinical presentation, spinal fluid examination, electrophysiology and all the challenges that go on from the
    team, to me, chances are [ninety-nine] percent that that diagnosis was correct.” Id. at 75.
    15
    from ongoing CIDP, Dr. Steinman testified, he would have expected to see the opposite (less
    reinnervation, and more dennervation). Id. at 120-21.
    Dr. Steinman specifically disputed the accuracy of changing Ms. Blackburn’s diagnosis
    to CIDP. He believed the improvement in her overall health by the spring of 2010 supported the
    conclusion that she merely suffered from a waxing and waning form of AIDP. Tr. at 124. He
    further noted that in his experience, AIDP patients often had incomplete recoveries – and that
    therefore this was an insufficient reason to alter a patient’s initial diagnosis. Id. at 62-63, 127-28,
    131. Dr. Steinman went on to observe that reflexes were present during this visit and continued
    to be present at every bodily site (including her ankles) at subsequent visits in the months to
    follow. Id. at 128-30. He admitted, however, that based on the very same treatment history, many
    of his colleagues would likely change a patient’s diagnosis to CIDP. Id. at 62-63.
    Finally, Dr. Steinman questioned the significance of Ms. Blackburn’s responsiveness to
    prednisone, asserting that steroids such as prednisone would inherently tend to make a patient
    feel less depressed and even “ebullient.” Tr. at 126-28. He added that he was not in favor of
    prednisone as a treatment due to its “nasty side effects.” Id. at 130. He later admitted, however,
    that prednisone was in fact indicated for CIDP34, but asserted that it represented a disfavored,
    last-ditch treatment when more standard treatments like IVIG had failed. Id. at 181-83. At
    bottom, Dr. Steinman felt that the mere temporal coincidence of corticosteroid treatment and
    continued recovery from a demyelinating episode was insufficient to establish CIDP as the
    correct diagnosis. Id. at 72.
    B.             Respondent’s Experts
    1.    Dr. Chaudhry – Respondent’s expert, Vinay Chaudhry, M.D., received his
    medical degree from All-India Institute of Medical Services in New Delhi, India. Tr. at 194;
    Resp’t’s Ex. B (Dr. Chaudhry’s curriculum vitae). He then went to England for secondary
    training where he obtained Membership in the Royal College of Physicians (M.R.C.P). Tr. at
    194. Thereafter, Dr. Chaudhry completed a residency in neurology at the University of
    Tennessee Center for the Health Sciences and the University of Alabama in Birmingham,
    followed by a two-year electromyography (“EMG”) and neuromuscular disease fellowship
    training program at Johns Hopkins University. Id. Dr. Chaudhry joined the faculty at John
    Hopkins in 1989, where he currently works as a professor of neurology, teaching and working on
    34
    Dr. Steinman also attacked Dr. Chaudhry’s contention that steroids are never to be used for treatment of GBS,
    arguing instead that they were in fact commonly used until it became clear that IVIG and plasmapheresis treatments
    were more successful. Tr. at 73-74.
    16
    clinical trials.35 Id. at 194, 196. He is board-certified in clinical neurophysiology, neuromuscular
    medicine, and electrodiagnostic medicine. Id. at 199. He has also published articles on a variety
    of topics, including GBS, with most of his publications pertaining to some aspect of peripheral
    neuropathy. Id.
    Despite his academic duties, Dr. Chaudhry spends the majority of his time caring for
    patients, including patients suffering from GBS, CIDP, and other neuromuscular diseases. Tr. at
    196-97. Most of Dr. Chaudhry’s outpatients suffer from CIDP, and he assists such individuals
    with diagnosis and management of long-term care. Id. at 196-98. Patients with GBS, by contrast,
    are typically so acutely ill that they require inpatient hospitalization (and then rarely return to the
    hospital thereafter because they have recovered), but one month a year Dr. Chaudhry sees GBS
    patients as well in conjunction with his work as an attending physician. Id. at 169, 208. Dr.
    Chaudhry also sees GBS patients for diagnostic purposes in the EMG laboratory at Johns
    Hopkins (where his responsibilities include acting as co-director of the laboratory, which is
    responsible for conducting about 5,000 of such studies per year), and he is directly experienced
    in conducting such tests and interpreting their results. Id. at 196-98, 218-19. Dr. Chaudhry
    estimated that over the course of his twenty-five year career, he has seen close to 30,000 patients
    with either GBS or CIDP. Id. at 197.
    Consistent with the opinions expressed in his written reports (see Resp’t’s Ex. A at 5;
    Resp’t’s Ex. XX at 2), Dr. Chaudhry testified that Petitioner’s CIDP diagnosis was correct.36 Tr.
    at 201-02, 209-41; See also Resp’t’s Ex’s E-J (medical or scientific literature relied upon by Dr.
    Chaudhry in formulating this opinion). While acknowledging that CIDP is a difficult diagnosis to
    make, even under the best circumstances (Tr. at 197-98), Dr. Chaudhry expressed the opinion
    that this is the diagnosis that all of Ms. Blackburn’s providers would have eventually made –
    even those who initially surmised that she suffered from AIDP – had they had the benefit of
    reviewing the totality of her medical records (including the clinical, electrophysiological,
    laboratory, and therapeutic features of her disease). Id. at 222-23, 249-51.
    Dr. Chaudhry reached his conclusion that Petitioner had CIDP largely based on the
    evidence of waxing and waning of her symptoms over a large period of time (including before
    her receipt of the HPV vaccination). Tr. at 239-41. Thus, he viewed the symptoms Ms.
    Blackburn exhibited in late 2008 as initial evidence of her CIDP. Id. at 210. Indeed, Ms.
    35
    Dr. Chaudhry’s involvement in clinical research includes serving as an investigator on research trials; for
    example, he was involved in the clinical trials that recently lead the FDA to approve IVIG for treatment of CIDP. Tr.
    at 200.
    36
    Dr. Chaudhry also opined that, given the diagnosis and the onset of symptoms that preceded the vaccination, he
    did not believe that the HPV vaccine played a significant role in Ms. Blackburn’s alleged injury. Tr. at 202. My
    decision does not, however, rely on this portion of his testimony (which was in fact mooted by Dr. Chaudhry’s
    testimony about the pre-vaccination course of Ms. Blackburn’s CIDP).
    17
    Blackburn’s initial symptoms were referred to as neuropathic or neuralgic several times in the
    contemporaneous medical records, and she was prescribed medications typically given to
    patients who are experiencing neuropathic or neuralgic conditions. Id. Dr. Chaudhry also found it
    significant that Dr. Zimmerman suggested performing tests aimed specifically at ruling out nerve
    injury, nerve damage, or neuropathy of some sort, such as nerve conduction studies.37 Id. at 228.
    And that Mr. Blackburn reported experiencing tingling in her legs and feet on the date of her July
    2009 vaccination (at which time she was still taking medication for her prior neuropathic
    symptoms). Id. at 211-12. Based on all of the above, Dr. Chaudhry concluded that Petitioner’s
    CIDP had likely begun in the second half of 2008. Id. at 227, 249-50.
    Dr. Chaudhry found further support for his opinion that Ms. Blackburn’s CIDP predated
    her vaccination in Petitioner’s August 19, 2009 EMG and nerve conduction study results (based
    on tests performed within a month of her vaccination). Tr. at 216-18. Having conducting
    hundreds of such tests over the years, Dr. Chaudhry indicated that he would expect a typical
    GBS patient to have EMG results displaying relative preservation (sparing) of sensory nerve
    action potentials. Id. at 216. Ms. Blackburn’s test results, however, showed no response in any of
    her sensory nerves. Id. He also observed reduced recruitment in her EMG results,38
    demonstrating to him that Ms. Blackburn already had a severe demyelinating neuropathy. Id. at
    217. Assuming Ms. Blackburn’s GBS began as a result of her July 2009 vaccination, it would be
    highly unusual for a patient to display such extensive damage in so short a time, whereas it
    would be common for CIDP (which would have progressed over a much greater length of time
    and begun many months before). Id. at 216, 218.
    On the other hand, Dr. Chaudhry opined that Ms. Blackburn did not display post-
    vaccination the kind of symptoms that he believed were consistent with a GBS diagnosis. Tr. at
    220. For instance, Ms. Blackburn presented with complaints of three-and-a-half weeks of
    ascending weakness and numbness on August 24, 2009, but when examined, Ms. Blackburn did
    not exhibit any facial weakness – her cranial facial nerve appeared normal. Id. at 219-22. Her
    upper extremities were also close to normal, which in Dr. Chaudhry’s view would be unusual for
    someone suffering from an acute disease like GBS that purportedly began about a month earlier
    (and should be at its most severe point by that time). Id. at 219-21.39 And he questioned Dr.
    37
    Even if her symptoms were not severe enough at this point for the doctor to order a lumbar puncture or nerve
    conduction studies, they still suggested to Dr. Zimmerman that he do preliminary testing, and start treating Ms.
    Blackburn with amitriptyline. Tr. at 226-28.
    38
    “In a normal recruitment pattern, the number of discharging motor units increases appropriately for the muscle
    force generated by the effort. In neuropathy, a loss of functional motor units results in late or decreased recruitment
    associated with rapid firing of discharging units to compensate for the reduced number.” Dyck & Thomas at 952-53
    (citations omitted).
    39
    Based on his review of the contemporaneous records and test results from Ms. Blackburn’s August 24th doctor’s
    visit, Dr. Chaudhry actually concluded that even if he accepted the GBS diagnosis, the time from onset at this point
    18
    Steinman’s belief that Ms. Blackburn’s post-hospitalization relapse was attributable to her not
    receiving a full course of IVIG treatment, since (based on the medical records) it appeared to Dr.
    Chaudhry that she had received a full course of treatment despite her anemic reaction. Id. at 224-
    25, 233-34.40
    The success of the prednisone course that Dr. Bromberg prescribed was in Dr.
    Chaudhry’s view particularly strong evidence that CIDP was the correct diagnosis. Tr. at 235-36,
    238-39. In discussing the benefit of prednisone for CIDP patients, Dr. Chaudhry took issue with
    Dr. Steinman’s suggestion that Ms. Blackburn felt better after receiving it simply because of its
    “euphoric effect.” Id. at 239. Dr. Chaudhry emphasized that Ms. Blackburn’s intervening
    medical history corroborated the benefit of the prednisone treatment, since her symptoms got
    worse whenever her dosage was removed or reduced. Id. In fact, when Dr. Bromberg began a
    slow taper of the prednisone, he started Ms. Blackburn on CellCept41 – a very strong steroid
    sparing agent that (in Dr. Chaudhry’s experience) would never be given to a patient believed to
    have GBS. Id. at 237. Nothing Dr. Chaudhry saw in Ms. Blackburn’s medical history suggested
    to him that the diagnosis change was in error, nor did any of her subsequent treating physicians
    believe that CIDP was a mistaken diagnosis in light of additional findings or data pertaining to
    her progress. Id. at 239-40, 249-50.
    Dr. Chaudhry addressed some of Petitioner’s arguments that Ms. Blackburn did not
    display any CIDP symptoms pre-vaccination. He acknowledged that Ms. Blackburn’s reflexes
    were recorded as normal when she received the vaccination as well as before, but opined that her
    other symptoms, viewed together, likely represented the beginning of a neuropathy. Tr. at 212-
    13. In his experience, however, it was typical for CIDP patients to experience a variety of mild
    neuropathic symptoms over a long period of time before receiving a CIDP diagnosis, despite the
    presence of normal reflexes.42 Id.
    He did not find significant the long gap between Ms. Blackburn’s early 2009 doctor’s
    visits and the post-vaccination flare-up she experienced, since in his view it was common for
    would have to have been longer than four weeks and closer to sixty days (six weeks or thereabouts), which is well
    outside the clinical definition for the disease’s four-week progression. Tr. at 221-22.
    40
    See Pet’r’s Ex. 7 at 25; Tr. at 224. Dr. Chaudhry’s understanding of what a full IVIF course would be is consistent
    with prominent medical literature on the subject. See, e.g., Dyck & Thomas at 642 (the standard course of IVIg “first
    used for autoimmune thrombocytopenia was 0.4g/kg daily for [five] days, and this has been adopted in
    neuromuscular diseases” (although the dose may be different for recurrent courses)).
    41
    CellCept (mycophenolate mofetil) is an immunosuppressive agent (Dorland’s at 1216) more commonly used for
    renal transplant patients. Tr. at 237.
    42
    Dr. Chaudhry speculated that Ms. Blackburn’s initial treatment providers may not have been as comprehensive in
    testing her reflexes (given the other warning signs present) as he would have given his experience. Tr. at 213.
    19
    CIDP patients to go a long time with low grade or intermittent symptoms while still being able to
    work. Id. at 206, 226. Dr. Chaudhry found it unlikely that a twenty-six year old would
    experience this type of nerve pain and tingling as the result of mere “physical stress” (Resp’t’s
    Ex. A at 6-7; Tr. at 227), and pointed to Dr. Zimmerman’s suspicion of neuritis or neuralgia as
    supportive of this view. Resp’t’s Ex. A at 6; Tr. at 228.
    2.      Dr. Whitton - James Lindsay Whitton, M.D. is an immunologist at
    Scripps, a nonprofit private research institution. Tr. at 269; Resp’t’s Ex. D (Dr. Whitton’s
    curriculum vitae). He serves on the editorial boards of several medical journals. Tr. at 272. Dr.
    Whitton has “only worked a little in molecular mimicry,” though he has had professional
    colleagues with greater expertise in the topic. Id. at 269, 362. Dr. Whitton’s testimony was
    offered in response to Dr. Steinman’s proposed theory by which the HPV vaccine could cause
    GBS. Dr. Whitton proposed that Dr. Steinman’s theory relied upon two core premises: (1)
    homology between the protein components of the HPV vaccine and the relevant target sites on
    the peripheral nerves; and (2) the induction of an immune response against MBP. Id. at 278-79.
    Dr. Whitton’s disputed both premises, arguing that (1) MBP is not the target antigen in GBS; and
    (2) Dr. Steinman’s homology theory is not scientifically valid.
    Dr. Whitton agreed with Dr. Steinman that molecular mimicry is a biologically plausible
    theory under certain circumstances. Tr. at 362-63. He similarly did not challenge Dr. Steinman’s
    general explanation for how molecular mimicry would occur. Id. at 281, 362. And he did not
    seriously question the assertion that GBS could be caused by molecular mimicry. See Resp’t Ex.
    C (Dr. Whitton’s Expert Report) at 4. Instead, Dr. Whitton challenged Dr. Steinman’s invocation
    of molecular mimicry in this particular case. Tr. at 306.
    First, Dr. Whitton questioned the application of Dr. Steinman’s homology theory to the
    autoimmune response specifically resulting in GBS. Tr. at 295. Dr. Whitton explained that
    peripheral nervous system diseases are generally thought to be driven by antibody responses
    rather than T cell mediated. Id. at 327. He acknowledged the literature establishing that MBP-
    specific T cells induce EAE in mice via molecular mimicry (Id. at 283-86), but asserted that such
    studies were of limited applicability here, as they involved an artificial stimulation of animal
    immune systems intended to produce a central nervous system disease that nevertheless did not
    also cause the test subject laboratory animals to develop peripheral nerve diseases. Id. at 281-83.
    In Dr. Whitton’s view, the “pathology and parthogenesis” of central nervous system neuropathies
    could not be properly conflated with peripheral nervous system neuropathies. Id. at 283.
    Importantly, Dr. Whitton argued, the MBP-specific T cells that have been shown in the
    EAE studies to target MBP have not been shown to have the same effect in causing peripheral
    nervous system diseases. Id. at 286. This, he elaborated, was due to the fact that there is no
    evidence that MBP is a possible target antigen in causing GBS. Id. at 287. Rather, he noted that
    20
    there are many other potential structures in peripheral myelin (of which MBP is a component)
    that could be the target of a demyelinating autoimmune response. Id. at 291. In particular, nerve
    gangliosides43 have been demonstrated to be the target in autoimmune-induced GBS via the
    process of molecular mimicry between the infectious agent and the ganglioside. Id. at 289-91;
    Tomoko Komagamine & Nobuhiro Yuki, Ganglioside Mimicry as a Cause of Guillain-Barré
    Syndrome, 5 CNS & Neurological Disorders 391-400 (2006) (Rep’t’s Ex. R at 6-7) [hereinafter
    “Komagamine”].
    Second, Dr. Whitton questioned the scientific validity of Dr. Steinman’s revised theory of
    homology. Dr. Whitton asserted that F and Y are in fact not generally interchangeable. Tr. at
    310. Moreover, Dr. Whitton argued that there is “nothing special about FK” (Tr. at 317),
    pointing out that the probability that a protein of 500 amino acids contains at least one FK
    sequence is about seventy-one percent. Id. at 314. Thus, according to Dr. Whitton, if, as Dr.
    Steinman proposed, a sequence of that short length were sufficiently homologous with MBP to
    induce an autoimmune response, then it would be reasonable to expect autoimmune diseases to
    be far more common than they actually are. Id. at 315-17.44
    III.          Medical Literature
    Both sides offered substantial scientific and medical literature.45 Petitioner submitted
    twenty-five articles relied upon by her expert in formulating an opinion in this case. This
    included ten articles initially relied upon by Dr. Steinman to provide a mechanistic explanation
    of how the HPV vaccine could cause neurological damage, and to support his opinion that Ms.
    Blackburn’s GBS was caused by her receipt of the vaccination in question.
    43
    The term ganglioside refers to any of a group of glycosphingolipids (ceramide and oligosaccharide) occurring in
    nervous system tissues. Dorland’s at 760,794.
    44
    Dr. Whitton also addressed whether it appeared from Ms. Blackburn’s medical history that she had suffered from
    GBS as a result of the vaccine rather than an antecedent infection, and also whether the proposed theory by which
    the HPV vaccine had caused Ms. Blackburn’s purported AIDP occurred in a medically-acceptable timeframe. See
    generally Tr. at 319-40. Because my decision turns on other aspects of Dr. Whitton’s testimony, however, or matters
    that he did not specifically address (such as the propriety of the GBS diagnosis), I do not review these additional
    portions of his testimony herein.
    45
    Although I do not reference or discuss in this decision every item of medical or scientific literature offered by the
    parties, I have read all of the submitted articles. Hazlehurst v. Sec'y of Health & Human Servs., 
    604 F.3d 1343
    , 1352
    (Fed. Cir. 2010) (indicating that on review it is not necessary to rely on the presumption that the finder of fact has
    reviewed all presented evidence unless he specifically states otherwise, where the opinion of the special master
    specifically refers to that evidence). See also Andreu v. Sec'y of Health & Human Servs., 
    569 F.3d 1367
    , 1379 (Fed.
    Cir. 2009) (“Although Althen and Capizzano make clear that a claimant need not produce medical literature or
    epidemiological evidence to establish causation under the Vaccine Act, where such evidence is submitted, the
    special master can consider it in reaching an informed judgment as to whether a particular vaccination likely caused
    a particular injury”) (emphasis added).
    21
    Respondent cites certain pieces of literature submitted by Petitioner as well as forty-seven
    additional articles relied upon by her experts in formulating their opinion in this case.
    Respondent initially submitted six articles used to support Dr. Chaudhry’s expert opinions,
    which consisted of literature addressing the possible competing diagnoses as well as whether the
    vaccination in question triggered Ms. Blackburn’s alleged illness. Respondent then submitted
    one additional article regarding the molecular pathogenesis of GBS. Respondent also submitted
    forty articles relied upon by Dr. Whitton to address the timing of the first onset of Petitioner’s
    neurological disease in relation to her receipt of vaccination, as well as the likelihood that Ms.
    Blackburn’s neurological disease was triggered by a prior infection rather than the HPV
    vaccination.
    IV.           Procedural History
    As noted above, Ms. Blackburn filed this petition in June 2010. Petition (ECF No. 1) at 2-
    3. Over the ensuing six months, she filed relevant medical records and an affidavit that she
    intended to rely upon to establish her entitlement to compensation, certifying completion of the
    record on January 13, 2011. ECF No. 17. Thereafter, on March 9, 2011, Respondent filed her
    Rule 4(c) Report (ECF No. 20 (“Resp’t’s Rep’t”)), asserting in it that Petitioner could not satisfy
    the test for establishing entitlement to a Vaccine Program award as set forth in Althen v. Sec’y of
    Health & Human Servs., 
    418 F.3d 1274
    , 1278 (Fed. Cir. 2005). Resp’t’s Rep’t at 14. Among
    other things, Respondent argued that the medical records did not themselves establish causation
    because none of Petitioner’s treating physicians provided a medical theory. 
    Id.
     Respondent also
    proposed that onset occurred before the vaccination, and/or was related to an antecedent
    infection, and further questioned the accuracy of the GBS diagnosis. Id. at 15.
    Ms. Blackburn subsequently filed additional medical records in support of her claim, and
    then filed a second statement of completion on August 21, 2011. ECF No. 25. A status report
    filed on that same date indicated that Petitioner’s counsel was preparing a demand letter to send
    on Petitioner’s behalf to Respondent with the aim of resolving this case through settlement. ECF
    No. 25. Such initial settlement efforts were unsuccessful, however.
    Petitioner requested and was granted a number of extensions of time to file an expert
    report in support of vaccine causation46 before she did so on July 30, 2012. ECF No. 36. On
    September 25, 2012, Respondent filed an unopposed motion requesting an extension of time to
    file her expert reports, which was subsequently granted. ECF Nos. 38-39. Thereafter, on
    November 27, 2012, Respondent filed two expert reports. ECF Nos. 40-45. The special master
    46
    On October 31, 2011, January 30, 2012, March 30, 2012, and May 30, 2012, Petitioner requested and was
    subsequently granted requests for an extension of time for filing an expert report in support of vaccine causation.
    ECF Nos. 27-31, 34-35.
    22
    formerly responsible for this case next conducted a telephonic status conference on December
    20, 2012, to discuss the merit of each party’s position in this case. ECF No. 46. During the
    conference, the parties again expressed the desire to explore the possibility of resolving this case
    through informal settlement negotiations prior to setting a date for an entitlement hearing. Id. But
    these additional settlement discussions proved unsuccessful, and so during a status conference on
    June 6, 2013 the case was set for hearing and the parties were instructed to complete the filing of
    relevant medical records as well as pre-trial briefs. ECF Nos. 55, 58.
    In early 2014, the parties filed some additional medical literature, prehearing memoranda,
    and other supplemental materials. Thereafter, in March of 2014 the matter was assigned to me
    (ECF Nos. 69-70) but the previously-scheduled hearing dates (March 25-26, 2014) were
    maintained and the matter was tried as scheduled. Both parties filed post-trial briefs in June (ECF
    Nos. 77-78) and then responded to each other’s filings in July (ECF Nos. 79-80). This matter is
    now ripe for adjudication.
    V.            Standards for Entitlement Award in Vaccine Program Cases
    To receive compensation under the Vaccine Program, a petitioner must prove either: (1)
    that she suffered a “Table Injury” – i.e., an injury falling within the Vaccine Injury Table –
    corresponding to one of the vaccinations in question, or (2) that her illnesses were actually
    caused by a vaccine (a “non-Table injury”). See §§ 300aa-13(a)(1)(A),11(c)(1); § 300aa-14(a), as
    amended by 
    42 C.F.R. § 100.3
    ; 300aa-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).47 No table injury is alleged in this case, so Ms.
    Blackburn must prove causation-in-fact.
    Petitioners bear the burden of demonstrating actual causation by preponderant evidence.
    Cedillo v. Sec’y of Health & Human Servs., 
    592 F.3d 1315
    , 1321 (Fed. Cir. 2010); § 300aa-
    13(a)(1). To do so, a petitioner must provide: “(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 preponderance standard requires
    a petitioner to demonstrate that it is “more likely than not” that the vaccine at issue caused his
    injury. Moberly, 
    592 F.3d at
    1322 n.2. 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
    47
    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
    decisions 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).
    23
    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). To determine if Petitioner has
    carried her burden, I must assess “the record as a whole” and may not make an entitlement
    decision in her favor based solely on her own claims “unsubstantiated by medical records or by
    medical opinion.” § 13(a)(1).
    Each of the Althen prongs requires a different showing (although the preponderant
    evidence standard applies to each, and the same evidence can be offered to prove more than one
    of the prongs). Under Althen prong one, petitioners must provide a “reputable medical theory”
    demonstrating that the vaccine can cause the type of injury alleged. Pafford, 451 F.3d at 1355-56
    (citations omitted). To satisfy this prong, 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). The theory must only be “legally probable, not medically or
    scientifically certain.” 
    Id. at 549
    .
    Petitioners may satisfy Althen prong one without resort to medical literature,
    epidemiological studies, demonstration of a specific mechanism, or by offering a theory that has
    general acceptance in the medical or scientific communities. 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.” Andreu, 
    569 F.3d at 1380
    .
    Often, however, establishing a sound and reliable medical theory requires that the parties
    present expert testimony in support of their claims. 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). Cedillo, 617 F.3d at 1339 (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
    ).
    24
    In other federal judicial fora (such as the district courts), the Daubert factors are
    employed by judges (in the performance of their evidentiary gatekeeper roles) to resolve
    admissibility questions, excluding 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 scientific
    evidence actually proffered and heard. Davis v. Sec’y of Health & Human Servs., 
    94 Fed. Cl. 53
    ,
    66-67 (Fed. Cl. 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”), aff’d, 420 F. App’x 923 (Fed. Cir. 2011). The flexible use of the Daubert
    factors to determine the persuasiveness and/or reliability of expert testimony in Vaccine Program
    cases has routinely been upheld. See, e.g., Snyder v. Sec’y of Health & Human Servs., 
    88 Fed. Cl. 706
    , 742-45 (2009).48
    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)). Weighing the relative persuasiveness of
    competing expert testimony, based on a particular expert’s credibility, is part of the overall
    reliability analysis to which special masters must subject expert testimony in Vaccine Program
    cases. Moberly, 
    592 F.3d at 1325-26
     (“[a]ssessments as to the reliability of expert testimony
    often turn on credibility determinations”); see also Porter v. Sec’y of Health & Human Servs.,
    
    663 F.3d 1242
    , 1250 (Fed. Cir. 2011) (“this court has unambiguously explained that special
    masters are expected to consider the credibility of expert witnesses in evaluating petitions for
    compensation under the Vaccine Act”).
    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, 956 F.2d at 1148. In evaluating
    whether this prong is satisfied, 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 trustworthy evidence, since they are created
    48
    Petitioner argued at length in her pre-trial submissions that Daubert had been incorrectly cited by Respondent
    because it is a tool for determining only if evidence was admissible, and therefore has less utility in evaluating the
    reliability, persuasiveness, or adequacy of expert testimony. See, e.g., Pet’r’s Pre-Hr’g Reply Mem., dated February
    18, 2014 (ECF No. 68) at 10-20. This is plainly against relevant controlling authority.
    25
    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 setting forth 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. § 300aa–13(b)(1) (providing that “[a]ny such diagnosis, conclusion,
    judgment, test result, report, or summary shall not be binding on the special master or court”);
    Snyder, 88 Fed. Cl. at 745 n.67 (“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”).
    Rather, 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 present in the record – including conflicting opinions among the treating
    physicians themselves. Hibbard v. Sec'y of Health & Human Servs., 
    100 Fed. Cl. 742
    , 749 (Fed.
    Cl. 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 (Fed. Cl. 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
    .
    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.”
    de 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.; Shapiro v.
    Sec’y of Health & Human Servs., 
    101 Fed. Cl. 532
    , 542 (Fed. Cl. 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
    , at *27 (Fed. Cl. Spec. Mstr.
    May 30, 2013), aff’d, No. 2014-5054, 
    2014 WL 6804880
     (Fed. Cir. Dec. 4, 2014).
    The law pertaining to the parties’ respective burdens of proof also merits brief mention.
    Petitioner has suggested that because Respondent argues that Ms. Blackburn actually suffered
    from CIDP rather than GBS, it is Respondent’s burden to establish Petitioner’s CIDP as a “factor
    unrelated” cause of Petitioner’s illness. See, e.g., Pet’r’s Pre-Hr’g Reply Mem. (ECF No. 68) at 2
    (citing Walther v. Sec’y of Health & Human Servs., 
    485 F.3d 1146
    , 1152 (2007)). It is correct
    that in cases where a petitioner successfully satisfies her initial burden of proof, the burden then
    shifts to Respondent to establish (also by the same preponderance of the evidence standard) that
    the petitioner’s injuries are due to “factors unrelated” to the vaccines. C.K. v. Sec’y of Health &
    26
    Human Servs., 
    113 Fed. Cl. 757
    , 766 (2013) (citing Knudsen, 
    35 F.3d at 547
    ); Deribeaux v.
    Sec’y of Health & Human Servs., 
    105 Fed. Cl. 583
    , 587 (2012), aff’d, 
    717 F.3d 1363
     (Fed. Cir.
    2013); 42 U.S.C. § 300aa–13(a)(1)(B).
    The burden of proof does not, however, shift to Respondent merely because (as in this
    case) she disputes the factual nature of the alleged injury or its proper diagnosis. On the contrary
    – Respondent may offer evidence, or point to existing evidence in the record, that contradicts or
    weakens a petitioner’s evidence, and in so doing demonstrate that the petitioner cannot meet her
    overall burden. Stone v. Sec’y of Health & Human Servs., 
    676 F.3d 1373
    , 1379 (Fed. Cir. 2012)
    (“[o]ur decisions support the commonsense proposition that evidence 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”); La Londe v. Sec’y of Health & Human Servs., 
    110 Fed. Cl. 184
    , 198 (2013)
    (“[r]egardless of whether the burden ever shifts to the respondent, the special master may
    consider the evidence presented by the respondent” when determining if petitioner’s initial
    burden has been met), aff’d, 
    736 F.3d 1334
     (Fed. Cir. 2014). In this case, Respondent’s challenge
    to the proper diagnosis of Petitioner’s illness does not amount to an attempt to establish a causal
    “factor unrelated,” and therefore in considering such issues I do not find that Respondent is
    burdened with proving them.
    VI.           ANALYSIS
    A.             Dispute Over Petitioner’s Diagnosis
    Both sides devoted a substantial portion of the hearing to addressing whether the HPV
    vaccine could be shown to cause GBS (or more precisely the AIDP variant of GBS). The
    medical records in this case, however, suggest a more immediate question: whether Ms.
    Blackburn had GBS at all, and/or whether her illness began only after her receipt of vaccination.
    Ms. Blackburn and her counsel did not originally plead a claim based upon significant
    aggravation of a pre-existing condition, and have otherwise repeatedly denied that they do so
    now. See generally Hirmiz v. Sec'y of Health & Human Servs., No. 06-371V, 
    2014 WL 7204716
    ,
    at *9-10 (Fed. Cl. Dec. 4, 2014) (failure to amend petition before trial to add significant
    aggravation was fatal to claim, despite fact that evidence offered at trial incidentally supported
    such a claim). Therefore, if the illness Petitioner suffered from was different from what was
    alleged, began before she ever received the HPV vaccination, and/or was not itself triggered or
    aggravated by the vaccination – then Petitioner’s entire claim cannot succeed.49
    49
    In his testimony, Dr. Steinman did claim that his theory for how the HPV vaccine could have caused Ms.
    Blackburn’s illness still applied even if she suffered from CIDP rather than the AIDP variant of GBS. Tr. at 186-89.
    However, he admitted that his theory was heavily focused on AIDP being the correct diagnosis, and he did not
    testify that Ms. Blackburn’s pre-vaccination symptoms were aggravated by the Gardasil vaccine – nor did he ever
    27
    As Federal Circuit precedent establishes, in certain cases it is appropriate to determine the
    precise nature of a petitioner’s injury before engaging in the Althen analysis. Broekelschen, 
    618 F.3d at 1346
    . Indeed, the fact that a claimed injury predates the vaccination can defeat a Vaccine
    Program claim entirely. Shalala v. Whitecotton, 
    514 U.S. 268
    , 274-75(1995) (Vaccine Act
    claimant who demonstrates she experienced symptoms of injury after receipt of vaccination does
    not succeed in her claim if the evidence fails to indicate that she had no symptoms of injury
    before her vaccination); Locane v. Sec’y of Health & Human Servs., 
    99 Fed. Cl. 715
     (2011)
    (petitioner’s Crohn’s disease began prior to her vaccinations and therefore vaccine causation
    could not be established). Since “each prong of the Althen test is decided relative to the injury”
    (Broekelschen, 
    618 F.3d at 1346
    ), determining facts relating to the claimed injury can be
    significant in a case like this, where the petitioner has symptoms predating her vaccination that
    could be consistent with an illness other than that alleged as the injury. Indeed, as another special
    master recently noted, “where the respondent presents evidence of an alternative diagnosis, the
    special master may consider the respondent’s evidence of that alternative diagnosis as part of the
    master’s evaluation of the petitioner’s prima facie showing of an injury, potentially mooting the
    Althen causation test.” Hirmiz, 
    2014 WL 7204716
    , at *14.
    Thus, before determining whether Ms. Blackburn has met each of the individual Althen
    prongs, I address whether she has established by preponderant evidence that she suffered from
    the AIDP variant of GBS, and whether her illness began prior to her vaccination.
    1.      GBS/AIDP vs. CIDP – As noted in the Koningsveld article50 included in
    the medical literature offered by Petitioner, GBS is an acute variant of an inflammatory
    demyelinating polyneuropathy. Pet’r’s Ex 36 at 1. It is a rapidly progressing and ascending
    motor neuron paralysis frequently seen after infection51 (Dorland’s at 1832), and it is typically
    monophasic. Pet’r’s Ex. 37 at 1. From a clinical diagnostic standpoint, an individual with GBS
    reaches the peak severity of his symptoms (nadir) within four weeks from initial onset.
    Koningsveld at 138.
    maintain that her earlier symptoms had anything to do with her post-vaccination illness. More significantly (and in
    keeping with the fact that Petitioner does not advance a significant aggravation claim in this case), Petitioner did not
    offer any testimony or medical literature explaining how (assuming Ms. Blackburn’s illness predated vaccination)
    the HPV vaccine could have worsened a pre-existing condition. I therefore could not find that Petitioner has offered
    preponderant evidence to satisfy a significant aggravation off-Table claim, even if such a claim had been alleged.
    50
    Ruts, L., Van Koningsveld, R., & Van Doorn, P.A., Distinguishing Acute-Onset CIDP from Guillain–Barré
    Syndrome with Treatment Related Fluctuations, 65 Neurol. 1, 138-40 (2005) (Pet’r’s Ex. 36) [hereinafter
    “Koningsveld”].
    51
    Odaka, M., Yuki, Nobuhiro, Y., Hirata, K., Patients with Chronic Inflammatory Demyelinating Polyneuropathy
    Initially Diagnosed as Guillain–Barré Syndrome, 250 J. Neurol. 913-16(2003) (Pet’r’s Ex. 35) [hereinafter
    “Odaka”].
    28
    AIDP is a common GBS variant (and is sometimes thought of as synonymous with the
    disease). P. Dyck & P.K. Thomas, 2 Peripheral Neuropathy 2199 (4th ed. 2005) [hereinafter
    “Dyck & Thomas”]. It shares the acute and monophasic characteristics of other GBS variants.
    Ted M. Burns, M.D., Guillain-Barré Syndrome, 28 Seminars in Neurol. 152-67 (2008) (Resp’t’s
    Ex. G at 3) [hereinafter “Burns”]; Dyck & Thomas at 2222. AIDP is considered to be immune-
    mediated, meaning that a triggering event (which may or may not be identified) occurs, leading
    to an aberrant immune response which in turn causes a breakdown of the blood-nerve barrier and
    destruction of the myelin sheath (and secondarily also the axon) resulting in the clinical
    presentation seen in an individual with AIDP. Wilson, H. J., The Immunobiology of Guillain–
    Barré Syndromes, 10 J. Peripheral Nervous System 94-112 (2005) (Resp’t’s Ex. O). Some of the
    symptoms included in the clinical definition of AIDP are: (a) numbness and tingling in the feet
    progressing in an ascending fashion to the arms; (b) progressive and ascending weakness; (c)
    areflexia; and (d) cranial nerve dysfunction/facial weakness. Amato, A. & Russell, J., 227
    Neuromuscular Disorders 213-14 (1st ed. 2006) (Pet’r’s Ex. 33) [hereinafter “Amato”]; Van
    Doorn, P.A., Ruts, L., Jacobs, B.C., Clinical Features, Pathogenesis, and Treatment of Guillain–
    Barré Syndrome, 7 Lancet Neurol. 939 (2008) (Resp’t’s Ex. F) [hereinafter “Van Doorn”]. Tests
    that can confirm or lend support to the diagnosis include a lumbar puncture (to determine
    elevation of protein levels in the cerebrospinal fluid) and EMG/nerve conduction studies. Van
    Doorn at 940, 950.
    CIDP is also a demyelinating condition with symptoms similar to AIDP, but typically
    presents in either a chronically progressive or relapsing-remitting form. Dyck & Thomas at
    2221-22. A CIDP patient’s neurologic symptoms develop over weeks and months (with eight
    weeks viewed as the minimum clinical period for a CIDP diagnosis), and an antecedent infection
    is much less commonly identified as the initiating factor for the illness. 
    Id.
     Facial muscle
    weakness and autonomic nervous system impairment are also less common in CIDP than in
    GBS. Id. at 2222-23.
    Despite their differences, distinguishing between the two diseases is difficult – in
    particular during their early phases. Koningsveld at 138; Odaka, M., Yuki, N., Hirata, K.,
    Patients with Chronic Inflammatory Demyelinating Polyneuropathy Initially Diagnosed as
    Guillain–Barré Syndrome, 250 J. Neurol 913-16 (2003) (Pet’r’s Ex. 35) [hereinafter “Odaka”]
    (“the difference between GBS and CIDP in some patients may be blurred during the first [four]
    weeks” – “physicians could classify patients with CIDP within [four] weeks of onset as GBS”).
    Patients whose symptoms are initially believed to be compatible with GBS may later be
    diagnosed with CIDP based on the subsequent course of illness. Koningsveld at 138. And when
    treatment is administered early in the course of disease, patients may actually experience a
    simulated GBS episode within the overall context of CIDP (thus causing further diagnostic
    confusion). Odaka at 914.
    It is important for clinicians to attempt to distinguish between CIDP and GBS as early in
    29
    the course of illness as possible because of differences in treatment and prognoses. Koningsveld
    at 138, 140. Although IVIG treatments are utilized successfully in resolving both GBS/AIDP and
    CIDP, corticosteroid treatments “provide clear-cut benefit for most patients with CIDP, whereas
    they were shown to be ineffective in AIDP.” Dyck & Thomas at 2223; see also Jean-Michel
    Vallat et al., Chronic Inflammatory Demyelinating Polyradiculoneuropathy: Diagnostic and
    Theraputic Challenges for a Treatable Condition, 9 Lancet Neurol. 403-12 (2010) (Res’p’t Ex. I
    at 7-8); Mori, K. et al., Chronic Inflammatory Demyelinating Polyneuropathy Presenting with
    Features of GBS, 58 Neurol. 979 (2002) (Pet’r’s Ex. 34) (corticosteroid therapy is not considered
    beneficial for GBS); Odaka at 916; Van Doorn at 939-50.
    Recurrences or treatment-related fluctuations have been seen in individuals with GBS.
    Hadden, R.D.M., Deterioration After Guillain–Barré Syndrome: Recurrence, Treatment-Related
    Fluctuation, or CIDP?, 80 Neurol. Neurosurg. Psychiatry 3 (2009) (Pet’r’s Ex. 37) [hereinafter
    “Hadden”]. A treatment-related fluctuation has been defined “as significant deterioration within
    [two] months after disease onset, following post-treatment improvement or stabilization,” which
    is thought to occur as a result of “relatively prolonged autoimmune activation outlasting the
    effect of treatment.” Id. Recurrent GBS is distinguished from CIDP by “very long asymptomatic
    periods with return of tendon reflexes, more frequent antecedent illness, rapid onset, frequent
    facial weakness and normal CSF protein within [one] week of onset.” Hadden at 3; Odaka at
    916.
    Both experts generally agreed on the above, but had slightly different interpretations of
    various elements of the two diseases. Dr. Steinman expressed the view that GBS and CIDP are
    on the same spectrum – with AIDP simply constituting a more acute form of demyelinating
    polyneuropathy than CIDP. Tr. at 61-62, 64; see also Marinos C. Dalakas, Advances in the
    Diagnosis, Pathogenesis and Treatment of CIDP, 7 Nature Reviews Neurol. 507-17 (2011)
    (Resp’t’s Ex. J) [hereinafter “Dalakas”]. He thus suggested that distinguishing between the two
    based on onset and/or length of progression of symptoms reflected an “arbitrary separation from
    subacute and chronic demyelinating polyradiculoneuropathy.” Tr. at 65 (quoting Richard A.C.
    Hughes & Jeremy H. Rees, Clinical and Epidemiologic Features of Guillain-Barré Syndrome,
    176 (Supp. 2) J. Infectious Diseases S92 (1997) (Resp’t’s Ex. L at 2)).52 Nevertheless, Dr.
    Steinman acknowledged that “CIDP differs from GBS [] by its time course, mode of evolution,
    prognosis, and responsiveness to steroids.” Tr. at 64.
    Dr. Steinman asserted that the presenting symptoms for each disease were different.
    Thus, areflexia and symmetry are classic aspects for the presentation of an individual with CIDP,
    52
    Dr. Steinman elaborated on this point by suggesting that neurologists are famous for wanting to either “lump or
    split” (see Tr. at 62), and thus temporal distinctions between the progressions of both conditions reflected a desire by
    neurologists responsible for defining clinical facets of each to “draw the line” rather than meaningfully distinguish
    what are otherwise closely-related illnesses. Id. at 65.
    30
    but not necessarily present in a patient with GBS. Tr. at 66, 68. He further testified that in his
    experience it typically takes areflexia approximately one month to six weeks to develop in an
    individual with CIDP, after which reflexes would not return. Id. at 66. As a result, Dr. Steinman
    indicated that he would be reluctant to diagnose a patient that had reflexes with CIDP – and he
    would view a patient whose reflexes recovered, but whose other related symptoms had not
    dissipated and appeared chronic, as still recovering from AIDP, rather than as manifesting CIDP.
    Id. at 63-64.
    Dr. Chaudhry, by contrast, emphasized that in his view (which he testified was consistent
    with the view of “all neuromuscular physicians”), CIDP and GBS represent two separate (if
    related) conditions rather than opposing points on the same disease spectrum – and that as such it
    would be incorrect to view CIDP simply as a chronic form of GBS. Tr. at 208-09. Rather, they
    are distinguishable in terms of their presentation, treatment, and prognosis. Id. at 208. Thus, GBS
    (and its most common variant in the Western world, AIDP) is characterized by its rapid and
    acute progression, with subsequent slow recovery over a period of time – there is typically no
    waxing and waning course.53 Id. at 202-04. He also noted that IVIG is currently the standard
    treatment for GBS. Id. at 204-05.
    CIDP patients also experience weakness and numbness, exhibit loss of reflexes, exhibit
    high spinal fluid proteins, and demyelination under conduction. Tr. at 206. A distinguishing
    characteristic of CIDP, however, is its chronic nature, defined by lengthy relapsing and remitting
    phases.54 Id. Dr. Chaudhry expressed the view that the clinical diagnostic definition of CIDP as
    needing to last at least eight weeks was misleading – in his experience the course of illness is
    typically far longer. Id. at 206-07. Indeed, Dr. Chaudhry testified that he has observed patients
    with CIDP see their progression of symptoms take more than a year to get to the point where
    treatment was considered or warranted. Id. Dr. Chaudhry also stressed the significance of
    prednisone as highly indicated for the successful treatment of CIDP. See generally Id. at 205-
    07.55 According to Dr. Chaudhry, Prednisone is not used to treat GBS – and in Dr. Chaudhry’s
    opinion it would be malpractice to administer it to a GBS patient. Id. at 236.
    53
    Dr. Chaudhry acknowledged that there is a subcategory of GBS referred to as “relapsing Guillain-Barré,” but he
    testified that in his view this diagnostic classification is limited to those patients who have an attack of GBS, recover
    completely, and then have another attack months or years later. Tr. at 257.
    54
    In fact, Dr. Chaudhry stated, CIDP typically lasts throughout an individual’s lifetime, with most patients requiring
    ongoing treatment, although a few patients do go into remission (approximately one-third probably less). Tr. at 207.
    55
    A distinct diagnostic criterion for CIDP (at least in 1975 when it was first described by Dr. Peter Dyck), before the
    availability of physiology and nerve conduction studies, was steroid responsiveness to a patient’s symptoms. Tr. ay
    205-06. Dr. Chaudhry noted that CIDP was actually termed “steroid responsive chronic relapsing remitting
    polyneuropathy” in the landmark 1975 paper in the journal Neurology. Id. at 206. Other medications used for
    treatment of CIDP (CellCept, Rituximab, Imuran, and Cyclosporine), Dr. Chaudhry testified, do not have evidence-
    based medicine supporting their effectiveness, but are often employed because they can have a steroid-sparing effect
    (allowing for a reduction in the amount of steroid that is required to be taken by the patient). Id. at 207.
    31
    2.     Petitioner’s Medical History Suggests Her Actual Illness was CIDP –
    Although there is contradictory evidence in the medical records, those record by themselves
    (viewed in their totality and without the benefit of expert interpretation) suggest that Ms.
    Blackburn more likely than not suffered from CIDP, rather than the AIDP variant of GBS.
    Ignoring for the moment Ms. Blackburn’s pre-vaccination medical history,56 the records
    establish that Ms. Blackburn began experiencing symptoms no earlier than August of 2009.
    Pet’r’s Ex. 2 at 9-11; Pet’r’s Ex. 8 at 4-5. Even after intense treatment in August and September
    of 2009, however – about eight weeks after Ms. Blackburn’s HPV vaccination (a period almost
    twice as long as the four-week onset of GBS symptoms in most cases (see, e.g., Koningsveld at
    138)) – it became evident that Ms. Blackburn was again ill. Pet’r’s Ex. 7 at 14-15; Pet’r’s Ex. 5
    at 363.
    Her symptoms continued to wax and wane well into the spring of 2010, nine months
    later. Pet’r’s Ex. 7 at 6-7. Indeed, the very fact that Petitioner continued to experience symptoms
    despite the initial AIDP diagnosis and immediate treatment specific to that illness was a factor
    that lead Dr. Bromberg to conclude that she likely was suffering from CIDP. Id. at 2, 8-9.
    Because AIDP and CIDP can be confused in their early stages, it is not surprising that the
    treating physicians who first examined Ms. Blackburn between August and October of 2009
    reached different conclusions from those treating her six months later.
    The successful alteration of Ms. Blackburn’s treatments also strongly supports the CIDP
    diagnosis. By April 2010, the fact that Ms. Blackburn’s symptoms had still not fully cleared
    prompted Dr. Bromberg to try a prednisone course, based on the reasonable medical inference
    that a demyelinating condition that waxed, waned, and/or relapsed over several months was not
    sufficiently acute or monophasic to constitute a GBS variant. Pet’r’s Ex. 7 at 8. The medical
    literature strongly associates prednisone with the successful treatment of CIDP. See, e.g.,
    Dalakas at 508. And in fact the prednisone worked. Pet’r’s Ex. 7 at 2-4.
    Petitioner unconvincingly objects to the CIDP diagnosis that the medical history reflects.
    She argues that I should give great weight to the views of some treating physicians (in particular,
    those who treated Ms. Blackburn in the two to three months after her vaccination and/or made
    56
    Ms. Blackburn’s pre-vaccination history lends some support to the CIDP diagnosis. She first reported foot and
    hand numbness in October 2008 (see Pet’r’s Ex. 4 at 2-3), and complained of numbness and tingling on the actual
    vaccination date in July 2009 (see Pet’r’s’ Ex. 2 at 11-12) – suggesting her condition existed for a long time prior to
    its significant flare-up in August 2009 (see Id. at 9-10). Admittedly, however, Ms. Blackburn’s pre-vaccination
    treatment history also contains evidence less supportive of CIDP, as certain clinically-significant diagnostic clues (in
    particular, areflexia) did not point toward any severe neuropathy (see, e.g., Pet’r’s Ex. 8 at 18), and her post-
    vaccination symptoms were self-evidently more severe than what she had experienced in the months before. Pet’r’s
    Ex. 2 at 9. I therefore do not find that the pre-vaccination medical history (taken alone, without the assistance of an
    expert’s review) is particularly strong evidence for either side’s position – although, when expert interpretation of
    that record is added to my analysis, the pre-vaccination history becomes far more significant.
    32
    the initial AIDP diagnosis) but not others. Tr. at 118-19, 126-28. Petitioner particularly maintains
    that the determinations of Dr. Whitesell (which the record unequivocally establishes were made
    within a month or two of Ms. Blackburn’s vaccination) should predominate over a determination
    made by Dr. Bromberg – despite the fact that Dr. Bromberg’s evaluations and observations took
    into account what had happened during the months that had passed from the time Ms. Blackburn
    first complained of post-vaccination symptoms.
    Unquestionably the views of treating physicians are important, but they are also properly
    subject to evidentiary weighing. Capizzano, 
    440 F.3d at 1326
    . The overall course of Ms.
    Blackburn’s treatment history supports giving less weight to the determinations of the treating
    physicians who first saw her. Dr. Whitesell and others reached immediate conclusions about the
    nature of Ms. Blackburn’s illness without the benefit of the evidence Dr. Bromberg later relied
    on, including the results of trying a different medication used almost exclusively for CIDP.
    Significantly, there is nothing in the record suggesting that any other treating physicians who
    saw Ms. Blackburn after the prednisone’s efficacy was established in treating her symptoms
    disagreed with Dr. Bromberg’s conclusion regarding her diagnosis. Dr. Whitesell’s initial
    diagnosis of AIDP may, at the time, have been reasonable and supportable based on the
    immediate evidence at hand – but ultimately it proved incorrect.57
    All in all, I must consider the treatment record as a whole in evaluating the evidence
    offered to establish Petitioner’s illness. § 13(a)(1). Here, the record alone supports the conclusion
    that the corrected diagnosis – CIDP – was more accurate, given (a) the relapsing course of Ms.
    Blackburn’s symptoms, and (b) the effectiveness of the prednisone treatment.
    3.      Respondent’s Expert Persuasively Confirmed Both the CIDP Diagnosis
    and its Pre-Vaccination Onset – In a case such as this, where expert testimony is offered to
    interpret medical records and/or contemporaneous tests performed on the petitioner, a special
    master necessarily determines the persuasiveness of each competing expert. See, e.g., Carrino v.
    Sec’y of Health & Human Servs., No. 08-0266-V, 
    2013 WL 3328903
    , at *11-20 (Fed. Cl. Spec.
    Mstr. June 6, 2013) (finding Respondent’s expert’s review of medical history and specific test
    results more persuasive than Petitioner’s expert’s review, in connection with determination that
    Petitioner did not suffer from GBS). This flows naturally from a special master’s duty to evaluate
    expert credibility in the process of weighing the evidence. Porter v. Sec’y of Health & Human
    Servs., 
    663 F.3d 1242
    , 1250 (Fed. Cir. 2011) (“[t]he Federal Circuit has “unambiguously
    explained that special masters are expected to consider the credibility of expert witnesses in
    evaluating petitions for compensation under the Vaccine Act”).
    57
    I also note that Dr. Whitesell’s opinion was itself somewhat qualified, conclusory, and not corroborated with any
    explanatory basis. See, e.g., Pet’r’s Ex. 3 at 66 (“I feel that this likely still represents slowly improving Guillain-
    Barré which can sometimes have a waxing and waning course . . . I feel that an alternative diagnosis of CIDP is less
    likely”).
    33
    Both experts were qualified to testify to the matters in dispute generally, but Dr.
    Chaudhry was better qualified than Dr. Steinman to opine on the nature and treatment of GBS
    and CIDP, and his testimony was more credible. His demonstrated, day-to-day experience in
    seeing patients and reviewing the results of tests most relevant to diagnosing demyelinating
    diseases rendered his opinion particularly trustworthy. He also persuasively grappled with the
    record, acknowledging contrary evidence rather than dismissing it out of hand. Dr. Steinman, by
    contrast, has had far less direct experience with GBS or CIDP patients over the past several
    years, and less frequently reviews the results of (let alone performs) EMGs and nerve conduction
    studies. His core competency is with MS and central nervous system diseases. While such
    illnesses have some relationship to the matters in dispute (as they also involve demyelinating
    conditions with some common symptoms) they are not equivalent. Petitioner called upon Dr.
    Steinman in this case to wear two hats as an expert – that of a diagnostic expert as well as a
    theory/Althen prong one expert – but the latter fit him far better than the former, and I found him
    less persuasive on diagnostic topics.
    Dr. Steinman’s reduced expertise on matters pertaining to the diagnosis and treatment of
    peripheral neuropathies was evident during the hearing (and particularly when he attempted to
    minimize the impact of evidence harmful to the Petitioner’s case). For example, Dr. Steinman
    strained in arguing that there was nothing notable about the positive results of Ms. Blackburn’s
    prednisone treatments, asserting that corticosteroids were simply another option for any GBS-
    related illness, and would invariably make a patient feel better regardless of their clinical impact
    on the underlying disease. Tr. at 73. But this is contrary to the medical literature submitted by
    both parties, all of which strongly suggests that prednisone is indicated only for the treatment of
    CIDP. Indeed, Dr. Chaudhry (who plainly possesses substantially more experience in diagnosing
    and treating both GBS and CIDP) characterized the use of prednisone for treatment GBS patients
    as medical malpractice.
    Dr. Steinman was similarly unpersuasive in his effort to frame CIDP as little more than a
    severe, lasting case of AIDP. Tr. at 62. While it is true that the two diseases have much in
    common and (especially early in their course) can be easily confused, they are distinguishable –
    and, given the difference in treatment and prognosis, need to be distinguished in order to better
    assist patients in recovering from either. See, e.g., Koningsveld at 138; Odaka at 913, 916. But
    Dr. Steinman did not establish that the recurrence and persistence of Ms. Blackburn’s symptoms,
    after her seemingly successful treatment in August through September of 2009, was properly
    attributed to either treatment fluctuations or a “recurring” form of AIDP. The medical record in
    fact does not suggest that any treatment related fluctuations occurred.58 And beyond some
    58
    Notations in Ms. Blackburn’s medical records indicate that she received “2 g/kg of IVIG treatment over three
    days” (Pet’r’s Ex. 7 at 7) and there is also a notation taken from pharmacy records stating that she “received 35
    g[rams] of IVIG on 08/25/2009, 35 g[rams] of IVIG on 08/26/2009, and 30 mg of IVIG on 08/27/2009.” Id. at 25.
    Dr. Chaudhry noted that there appeared to be a typographical error in the pharmacy notation – Ms. Blackburn would
    have more likely received 30 grams (not milligrams) for her final IVIG dose, adding up to a total dosage of 100
    grams. Tr. at 224. In Dr. Chaudhry’s view, this is consistent with the standard dose for someone of her stature (as
    34
    medical literature stating that a fluctuating form of AIDP exists, the only support for this
    alternative diagnosis is Dr. Steinman’s ipse dixit, rather than evidence drawn from the record.
    Dr. Steinman failed to provide an overarching explanation for Ms. Blackburn’s illness
    based on the totality of her medical history. Thus, he placed excessive reliance on Dr.
    Whitesell’s October 2009 determination that CIDP was not likely the correct diagnosis for
    Petitioner – while giving less weight to the subsequent determination of Dr. Bromberg (as well
    as every other treating physician thereafter) that CIDP was in fact the correct diagnosis. Dr.
    Whitesell’s opinion itself contains no record support or corroboration explaining why she
    discounted the possibility of a CIDP diagnosis. See Pet’r’s Ex. 3 at 66. Dr. Bromberg, by
    contrast, had the benefit of months more of evidence regarding Petitioner’s condition, plus the
    fact that the test he proposed for determining if CIDP were the correct diagnosis (the prednisone
    treatment) worked. Dr. Steinman generally found more significant the initial diagnosis Ms.
    Blackburn received – a diagnosis that circumstances, and time, reasonably led her subsequent
    treating providers to re-evaluate. See, e.g., Pet’r’s Ex. 7 at 8. Dr. Steinman’s interpretation
    favored the position that once AIDP had been diagnosed, it remained the “correct” diagnosis
    even if later treatment evidence contradicted it. Tr. at 63.
    Dr. Steinman was also selective in what symptoms he deemed significant versus those he
    ignored. Thus, he overemphasized areflexia as a symptom of CIDP (thus rendering its absence
    from Ms. Blackburn’s pre-vaccination medical history a telling fact).59 Yet the literature offered
    by the parties more definitively identifies areflexia as a presenting symptom of GBS. See, e.g.,
    Burns at 3 (in GBS, “[w]idespread areflexia or hypoflexia is the rule”); Amato at 214 (Pet’r’s Ex.
    33 at 2). In so doing, Dr. Steinman ignored the fact that Ms. Blackburn did not display upper
    limb areflexia as of mid-August 2009 (see Pet’r’s Ex. 4 at 4-5), even though she would then have
    reached, if not be approaching, the nadir of her GBS (assuming, as Dr. Steinman opined, that her
    illness began with her July vaccination). At the same time, Dr. Steinman consistently
    downplayed the importance of cranial nerve weakness or dysfunction as a presenting symptom
    of GBS (Tr. at 71) – even though it is considered such (Van Doorn at 939-50) – and thus
    sidestepped the fact that Ms. Blackburn never displayed this particular symptom during her
    purportedly acute AIDP phase in August and September of 2009. Tr. at 91.
    the medical records indicate that she was five foot four inches and weighed approximately 104 pounds around this
    period of time. Id.; see also Pet’r’s Ex. 7 at 12. The medical literature corroborates Dr. Chaudhry’s view. See, e.g.,
    Dyck & Thomas at 642-43. Nothing else in the record indicates that Ms. Blackburn did not receive a full course of
    IVIG.
    59
    In any event, as Dr. Chaudhry later explained, individuals suffering from CIDP often experience a slow, long-term
    ramping up of the illness, during which common presenting symptoms might remain mild for a long period of time,
    and therefore the absence of clear areflexia before vaccination does not discredit the ultimate conclusion (bulwarked
    by a comprehensive review of the record) that CIDP was the correct diagnosis. Tr. at 206-7.
    35
    Dr. Chaudhry, by contrast, rooted his opinion in a complete view of the record. Having
    treated numerous CIDP patients (Tr. at 196-97), he was well qualified to observe that a patient
    may experience a number of mild neuropathic symptoms long before they are actually diagnosed
    with CIDP (and even before such a diagnosis might be proper). Id. at 206-07, 226. Because of
    the chronic nature of their symptoms, CIDP patients can “live” with the condition without
    hospitalization for a long time, as opposed to the acute, fast-moving nature of AIDP. Dr.
    Chaudhry credibly explained why Ms. Blackburn’s early examinations and test results did not
    display all of the formal clinical indicia of CIDP. Id. at 212-13.60 There were enough other signs
    to see, in retrospect, a relationship between Ms. Blackburn’s pre-vaccination neuropathic
    symptoms and her illness’s subsequent course. Id. at 227, 249-50.
    Dr. Chaudhry was also persuasive in identifying inconsistencies in Ms. Blackburn’s
    history from August to September 2009 that undercut the initial AIDP diagnosis. Through his
    reading of contemporaneous EMG test results, he pointed out convincingly that early symptoms
    and test results actually better supported the CIDP diagnosis – the nerve damage, for example,
    evident from Ms. Blackburn’s August EMG (see Pet’r’s Ex. 4 at 7) was too extensive to have
    occurred in the weeks immediately after her July 23rd vaccination, but was more likely evidence
    of a pre-existing illness that had to have begun before that date. Tr. at 216, 218.
    At bottom, Dr. Chaudhry was more persuasive in commenting on what was (or was not)
    relevant in diagnosing GBS and CIDP – based on evidence from contemporaneous medical
    records before and after Petitioner’s vaccination. In so doing, he convincingly offered an
    interpretation of the medical history that Petitioner has not rebutted – that it is improbable that
    Petitioner suffered from AIDP only beginning with her Gardasil vaccination.
    B.             Application of Althen Prongs
    Although my determination that Ms. Blackburn did not suffer from AIDP, and that her
    illness began before her vaccination, potentially obviates the need for an extensive Althen
    analysis, I nevertheless consider below each of its prongs based on the evidence presented.
    1.      Prong One: Can the HPV Vaccine Cause GBS and/or CIDP? Petitioner
    offered little direct evidence supporting her theory that HPV vaccine can cause GBS, other than
    VAERS reports,61 or research and case studies involving other vaccines which Petitioner argues
    60
    Respondent’s medical literature supported the idea that areflexia is not necessarily a sine qua non symptom of
    CIDP even if it is associated with the disease. See, e.g., Dalakas at 2-3 (CIDP characterized generally by “a
    progressive, symmetric, proximal and distal muscle weakness, paresthesias, sensory dysfunction, and impaired
    balance”).
    61
    “VAERS” refers to the Vaccine Adverse Event Reporting System. The value of a specific VAERS report as
    evidence in proving causation in a Vaccine Program case is extremely limited. As another special master has
    observed,
    36
    are analogous.62 There is, however, persuasive scientific evidence on the other side of the
    question. As Dr. Steinman admitted, the Institute of Medicine (“IOM”) has determined that
    “[t]he epidemiologic evidence is insufficient or absent to assess an association between HPV
    vaccine and GBS.” Tr. at 81-82; see also Adverse Effects of Vaccines at 512.63 Nevertheless,
    there is no specific category of evidence that a petitioner must offer to establish a medical theory
    supportive of a causation finding (Althen, 
    418 F.3d at 1280
    ), and therefore Petitioner’s inability
    to marshal this kind of specific scientific proof does not mean she cannot meet the requirements
    of the first Althen prong.
    Molecular mimicry theories have been accepted in other Vaccine Program cases as a
    general framework for explaining the development of certain autoimmune diseases (although
    such acceptance has not always resulted in entitlement decisions favorable to petitioners).
    Tompkins v. Sec’y of Health & Human Servs., No. 10-261V, 
    2013 WL 3498652
    , at *22 (Fed. Cl.
    Spec. Mstr. June 21, 2013) (“[t]he molecular mimicry theory is the one most widely accepted for
    the agents most frequently accepted as causal”), motion for review den’d, Tompkins v. United
    States, 
    117 Fed. Cl. 713
     (2014). Dr. Whitton conceded that molecular mimicry may explain
    vaccine-induced demyelinating injuries, as long as its basic requirements are met (Tr. at 362),
    and Respondent ultimately did not seriously question that this theory offers a potential
    explanation for how autoimmune diseases like GBS develop. See Resp’t Mem. at 23-27. But
    accepting that molecular mimicry has previously been found to be a reasonable general theory64
    VAERS is a stocked pond. It only contains reports (many of which are unverified or incomplete) of adverse
    events after vaccinations. VAERS contains no reports or data about the relative rate of these same events in
    individuals who have not been vaccinated. Thus, the number of specific adverse events, such as GBS,
    reported after any vaccine, is meaningless without information about the background rate of that adverse
    event and information about the number of vaccines administered.
    Tompkins v. Sec’y of Health and Human Servs., No. 10-261V, 
    2013 WL 3498652
    , at *16 (Fed. Cl. Spec. Mstr. June
    21, 2013), motion for review den’d, Tompkins v. United States, 
    117 Fed. Cl. 713
     (2014).
    62
    Respondent also questioned Petitioner’s reliance on research pertaining to central nervous system diseases, such
    as MS in humans and EAE in rodents. Resp’t’s Pre-Hr’g Mem. (ECF No. 62) at n. 7. Respondent further questioned
    the evidence showing homology between Y and F in mouse models, arguing that it did not constitute scientifically
    reliable evidence that they are interchangeable when dealing with human models. Respondent’s Reply to Pet’r’s
    Post-Hr’g Brief (ECF No. 79) at 5. While acknowledging that animal models have been found to be sufficient in
    some Vaccine Program cases, I do not specifically address this contention as it does not have a direct bearing on my
    decision in this case.
    63
    IOM evidence is especially reliable and useful in gauging whether a vaccine “can cause” a given injury. See
    generally Crutchfield v. Sec’y of Health & Human Servs., No. 09-0039V, 
    2014 WL 1665227
    , at *16 (Fed. Cl. Spec.
    Mstr. Apr. 7, 2014) (“[d]uring the 25–year history of the Vaccine Act, special masters have consistently relied upon
    the reports of the Institute of Medicine, and reviewing judges have consistently indicated approval of such
    reliance”).
    64
    I do not mean to say that the molecular mimicry theory is in all cases reasonable. On the contrary – the theory has
    at times been misused by certain experts, who have invoked it as a universal mechanism that can explain virtually
    any demyelinating or other autoimmune condition. See, e.g., Hennessey v. Sec'y of Health & Human Servs., 
    91 Fed. 37
    does not complete my analysis under Althen prong one – the theory offered must have
    application to this case. See Caves, 100 Fed. Cl. at 135 (noting that the Althen requirement to
    offer medical theory would be meaningless if petitioner did not need to apply molecular mimicry
    specifically to her case); Broekelschen, 
    618 F.3d at 1345
    .
    Respondent generally questioned whether Dr. Steinman’s corrected-on-the-witness-stand
    homology theory (which posits a mechanism for how the HPV vaccine could result in a
    peripheral neuropathy) has been shown to be scientifically reliable. Resp’t Pre-Hr’g Mem. (ECF
    No. 62) at 18; Tr. at 168-69. A petitioner need not necessarily demonstrate the precise homology
    involved when invoking molecular mimicry as the mechanism for explaining how a particular
    vaccine could cause injury. See, e.g., Salmins v. Sec’y of Health & Human Servs., No. 11-140,
    
    2014 WL 1569478
     (Fed. Cl. Spec. Mstr. Mar. 31, 2014) (granting entitlement in HPV/GBS case
    when petitioner relied on molecular mimicry without showing homology). But because the
    homology question was hotly disputed, I will review the evidence on the point pro and con.
    Dr. Steinman’s homology theory is inconsistent – particularly the manner in which he
    conflates autoimmune responses involving antibodies produced by B cells with those involving T
    cells. See Tr. at 17, 46; Pedro J. Ruiz et al., Microbial Epitopes Act as Altered Peptide Ligands
    to Prevent Experimental Autoimmune Encephalomyelitis, 189 J. Experimental Med. 1275 (1999)
    (Pet’r’s Ex. 21). The medical literature cited by the parties does not support the notion that this
    homology “works” regardless of whether the autoimmune response involves T cells or B cell
    antibodies.65 If limited to the context of T cell mimicry, however, there is better support for his F
    and Y equivalence argument in the context of an attack on MBP.66 Tr. at 157-60.
    Cl. 126, 134-35 (2010) (noting expert’s overly broad application of the molecular mimicry theory made it
    meaningless).
    65
    In his expert reports and testimony, Dr. Steinman invoked Wucherpfennig for the proposition that the FKN
    sequence is of particular importance to the homology between T cells and B cell antibodies, on the one hand, and
    MBP on the other. Tr. at 44. He then immediately jumped to a different study (Grada M. van Bleek & Stanley G.
    Nathanson, The Structure of the Antigen-Binding Groove of Major Histocompatibility Complex Class I Molecules
    Determines Specific Selection of Self-Peptides, 88 Immunology 11032 (1991) (Pet’r’s Ex. 32) [hereinafter “van
    Bleek”]) to support his assertion that F and Y are “pretty much interchangeable.” Tr. at 46-47. The van Bleek study,
    however, demonstrates only that Y and F are interchangeable in the specific context of binding T cells to mouse
    MHC class I molecules. Van Bleek at 11035.
    Dr. Whitton challenged the relevance of this study to humans (Tr. at 305-06), referencing Wucherpfennig (Pet’r’s
    Ex. 18 at 1117-18) to demonstrate that substituting Y for F has a “profound effect on immune recognition” in
    humans. Tr. at 311. The Wucherpfennig study specifically finds that F and Y are not interchangeable in the context
    of human autoantibody recognition. Wucherpfennig at 1116. Indeed, Wucherpfennig suggests that a YKN sequence
    is too limited to trigger cross-reactive antibodies (even assuming arguendo that F and Y were interchangeable),
    because “autoantibody recognition of microbial peptides required sequence identity over a stretch of four or five
    amino acids.” Id. at 1119.
    66
    The HFFK sequence of MBP is its “core motif” recognized within the T cell epitope. Pet’r’s Ex. 21 at 1275.
    Within this sequence, “K91 is the major TCR contact site, while F90 is a major anchor to MHC.” Id. Thus, the cited
    medical literature supports the concept that the two-acid FK sequence is indeed critical, and that limited peptide
    38
    Respondent argued that the FK/FY sequence is too common. Tr. at 313-14. If a two-
    protein homology is sufficient for cross-reactivity, she asserted, then the majority of microbes
    could serve as the basis for molecular mimicry in so many circumstances that the theory would
    be “so broad as to be meaningless.” Hennessey, 91 Fed. Cl. at 135; Tompkins, 
    2013 WL 3498652
    , at *23. Petitioner responded that because structural similarity is what drives Dr.
    Steinman’s molecular mimicry theory, little sequential homology is required for T cell mimicry
    to occur. See Rafael L. Ufret-Vincenty, In Vivo Survival of Viral Antigen-Specific T Cells that
    Induce Experimental Autoimmune Encephalomyelitis, 188 J. Exp. Med. 1726 (1998) (Pet’r’s Ex.
    23).
    Respondent also challenged the precise mechanism offered by Petitioner to explain how
    the autoimmune process resulting in GBS would function. Dr. Steinman’s homology analysis
    depends upon MBP as the target antigen. See, e.g., Pet’r’s Pre-hr’g Mem. (ECF No. 60) at 15-16;
    Tr. at 162-63. But as Dr. Whitton testified, available scientific evidence (reflected in the
    literature offered in this case) suggests that MBP is not the target antigen in autoimmune
    responses that result in a peripheral neuropathy like GBS. Tr. at 317, 327. Rather, other protein
    structures on the peripheral myelin have been demonstrated as far more likely targets of a
    demyelinating process. Id. at 290-94. Indeed, the “most solid evidence for a molecular mimicry”
    mechanism producing GBS (as Dr. Steinman acknowledged) involves an immune response
    against gangliosides. Id. at 162-63 (Dr. Steinman admitting that studies of the “Campylobacter
    story” involve attacks against gangliosides, “a different molecular mimic” from MBP);
    Komagamine at 394; see also Daily v. Sec’y of Health & Human Servs., No. 07-173V, 
    2011 WL 2174535
    , at *3 (Fed. Cl. Spec. Mstr. May 11, 2011) (“[a] large body of literature links
    gangliosides and antibodies against certain gangliosides as causal agents of GBS”).
    In support of her contention that MBP is the target antigen, Petitioner offered only the
    Cornblath study, which found increased MBP in the spinal fluid of patients suffering from GBS.
    Tr. at 162; Cornblath at 370. But the Cornblath study does not conclude that MBP is the target
    antigen in GBS – as Dr. Steinman admitted. Id. at 371; see also Tr. at 30-31, 162-63, 288-89.
    MBP is simply one of many other proteins and structures contained in peripheral myelin, and has
    been found to be released after the destruction of that myelin. Tr. at 180; Steinman, L. &
    Oldstone, M.B.A., More Mayhem from Molecular Mimics, 3 Nature Medicine 1322 (1997)
    (Pet’r’s Ex. 20). Otherwise, none of the medical literature cited by Petitioner identifies MBP as a
    potential target of an immune response that triggers GBS. See Amato at 217 (“[t]he nature of the
    epitope is not known but probably is a glycolipid”); Komagamine at 394-95 (listing candidate
    target molecules but omitting MBP). Nor has Petitioner offered any instances in which MBP as
    the target antigen has been tested (at least in the context of a peripheral neuropathy like GBS).
    substitutions (such as Y for F) would not necessarily hinder the activation of cross-reactive T cells with homologous
    protein sequences comprising MBP. Wucherpfennig at 1116, 1119-21.
    39
    Petitioner otherwise relied on studies establishing attacks on MBP pertaining to MS rather than
    peripheral neuropathies like GBS. Tr. at 283-86.67
    Overall (and despite the fact that precise homology has not been required in other cases
    to successfully establish a medical theory in satisfaction of the first Althen prong), I found the
    evidence offered by Petitioner in support of her molecular mimicry theory to be less persuasive
    than Respondent’s arguments to the contrary. However, even if I assume for sake of argument
    that Petitioner has offered just enough probative and reliable evidence to establish this first
    element of the causation test, such a determination would not aid her case. Hirmiz, 
    2014 WL 4638375
    , at *14. Because Ms. Blackburn has not demonstrated that she suffered from a vaccine-
    caused injury (give the above-discussed CIDP diagnosis and evidence that it predated her
    vaccination), the fact that the HPV vaccine could in theory cause a GBS variant other than the
    disease she actively suffered from is irrelevant to meeting her burden of proof.68
    2.      Prong Two: Did the HPV Vaccine Cause Ms. Blackburn’s GBS and/or
    CIDP? – There is support in the treatment record establishing a “logical sequence of cause and
    effect” between the receipt of the HPV vaccine and the demyelinating symptoms Ms. Blackburn
    later suffered – assuming GBS were her illness, and that it arose only after the vaccination. At a
    minimum, the record contains statements by Ms. Blackburn’s treating physicians that
    Petitioner’s initially-diagnosed AIDP was caused by her vaccination – and although many of
    those opinions seem based on the timing between vaccine and injury, that fact alone does not
    render their opinions without value.
    My determination that Ms. Blackburn’s illness was more likely than not CIDP rather than
    GBS, and that it predated her vaccination, however, precludes a finding that the Gardasil vaccine
    likely caused her injury. This determination is based on expert testimony and the treating
    records, which clearly reflect that Petitioner’s diagnosis was ultimately changed and has never
    been changed back since the time Ms. Blackburn received prednisone. The same evidence
    supports the conclusion that her illness more likely than not predated her vaccination, given the
    history of the neuropathic symptoms she has suffered.
    Petitioner was unable to rebut the above. Thus, while she pointed out facts from the
    67
    Those studies were also distinguishable for other reasons. For example, as Dr. Whitton noted, some involved
    experimentally-induced immune reactions (Tr. at 281-82) that were intended to produce central nervous system
    diseases like MS by significantly amplifying the intensity of the immune response – and therefore it was telling that
    they did not also produce a similar response in the peripheral nerves. Id. at 286-87, 325. Dr. Steinman himself
    ultimately admitted that EAE is not an acceptable model for GBS. Id. at 27, 169-70. At best, Dr. Steinman
    mentioned during his testimony an eighty year-old purported study, in which he claimed EAE-mice were found to
    have diseases of both the peripheral and central nervous system. Id. at 58. But that study was not filed in this case
    and has not otherwise been identified by Petitioner.
    68
    I also note that Petitioner’s Althen one theory does not address the idea of CIDP as being caused by the HPV
    vaccine – and indeed, Dr. Steinman strenuously challenged the accuracy of the CIDP diagnosis generally (even
    while asserting that his theory worked in either case).
    40
    treatment record that reasonably led Ms. Blackburn’s treating providers to assume at the outset
    that she suffered from AIDP, she failed to explain the overall thrust of the record – and in
    particular the waxing and waning course of the disease she experienced – beyond some general
    references to “fluctuating” GBS. Nor did she rebut the effectiveness of the prednisone
    treatments, or the changed diagnosis. Dr. Steinman for his part was too selective in his review of
    the record, overemphasizing aspects of it that favor Petitioner’s case while not effectively
    addressing the fundamental facts that point to CIDP as her real illness.
    My analysis would be the same even if Petitioner had accepted the revised CIDP
    diagnosis but still argued that the HPV vaccination caused it. There is no question that Ms.
    Blackburn experienced a flare-up of her symptoms temporally after receiving the Gardasil
    vaccine – but it is well understood in Program cases that a mere temporal association between
    vaccination and illness does not establish causation. Moberly, 
    592 F.3d at 1323
    . As CIDP is
    clinically understood to involve a longer course, the relatively acute symptoms Petitioner
    experienced in the weeks after the vaccination are not consistent with the chronic nature of the
    illness, which would be slower to develop. And the neuropathic symptoms she experienced well
    before (and even the day of) her July 23rd vaccination also suggest that her disease preceded her
    vaccination.
    3.     Is there a Medically-Acceptable Temporal Relationship? – Less than a
    month passed between Ms. Blackburn’s vaccination and the severe symptoms initially thought to
    be caused by AIDP. See, e.g., Pet’r’s Ex. 8 at 4-5. In addition, the record indicates that a few of
    her health care providers between August and October of 2009 believed (based on the
    information they possessed at the time) that temporally the vaccine likely had caused the
    symptoms they both observed and treated. See, e.g., Pet’r’s Ex. 4 at 9. Certainly there is support
    (in both the relevant medical literature as well as the decisions of other special masters) for the
    conclusion that the timeframe between vaccination and Ms. Blackburn’s temporally-subsequent
    symptoms was medically acceptable – again, assuming she suffered from GBS. See, e.g., Corder
    v. Sec’y of Health & Human Servs., No. 08-228V, 
    2011 WL 2469736
    , at *27-29 (Fed. Cl. Spec.
    Mstr. May 31, 2011) (proposed four-month onset period from vaccination to GBS too long; two
    months is longest reasonable timeframe).
    But Petitioner has not established that she more likely than not suffered from GBS. And
    even if Petitioner had accepted the CIDP diagnosis and argued that it was caused by the July
    2009 vaccination (rather than predating it), there would still be a lack of a medically-acceptable
    temporal relationship, due to the fact that (as none of the parties disputed) the course of CIDP is
    considerably longer than AIDP. CIDP would less likely become as acute (as the records establish
    Ms. Blackburn’s illness was) within a month of vaccination, and no evidence offered by
    Petitioner or her expert alters this conclusion. Thus, Petitioner’s claim also founders on her
    inability to meet the third Althen prong.
    41
    CONCLUSION
    I have great sympathy for the medical problems and related suffering Ms. Blackburn has
    experienced over the past several years. However, a petitioner who fails to demonstrate by a
    preponderance of the evidence that the vaccine she received was more likely than not the cause
    of her illness is not entitled to compensation. Such is the case here. Because Ms. Blackburn has
    failed to demonstrate that she in fact suffered from injuries caused by her receipt of the HPV
    vaccine, I DENY an entitlement award in this case. I instruct the Clerk of Court to enter
    judgment dismissing the case unless a motion for review is filed.
    IT IS SO ORDERED.
    s/Brian H. Corcoran
    Brian H. Corcoran
    Special Master
    42