Court Opinion

ID: 9370128
Source: CourtListenerOpinion
Date Created: 2023-02-10 21:01:22.123178+00
Date Added: 2024-06-11T17:16:20.209336
License: Public Domain

REDACTED OPINION
            In the United States Court of Federal Claims
                                     No. 16-989V
                               Filed: October 17, 2022
              Redacted Version Issued for Publication: February 10, 20231

    * * * * * * * * * * * * * *           *
                                          *
    K.A.,                                 *
                       Petitioner,        *
                                          *
                v.                        *
    SECRETARY OF HEALTH AND               *
    HUMAN SERVICES,                       *
                                          *
                      Respondent.         *
                                          *
    * * * * * * * * * * * * * *
                                          *

        Robert J. Krakow, Law Office of Robert J. Krakow, P.C., New York, NY, for
petitioner.
       Nina Ren, Trial Attorney, Torts Branch, Civil Division, United States Department
of Justice, Washington, DC, for respondent. With her were Heather L. Pearlman,
Assistant Director, Torts Branch, C. Salvatore D’Alessio, Acting Director, Torts Branch,
Brian M. Boynton, Principal Deputy Assistant Attorney General, Civil Division.
                                     OPINION

HORN, J.

       On August 11, 2016, petitioner K.A. filed a petition for compensation with the
National Vaccine Injury Compensation Program (Vaccine Program), under the National
Childhood Vaccine Injury Act of 1986, 42 U.S.C. §§ 300aa-1–300aa-34 (2018) (Vaccine
Act), for an off-Table injury. See 42 U.S.C. § 300aa-11(c)(1)(C)(ii) (2018). Petitioner
claimed that an August 12, 2013 Tetanus Diphtheria acellular-Pertussis (Tdap)
vaccination caused him to experience Guillain-Barré syndrome. On April 18, 2022, Chief
Special Master Brian H. Corcoran denied petitioner’s claim for an award of

1  This Opinion was issued under seal on October 17, 2022. Petitioner proposed
redactions to the Opinion, which were incorporated into this version. The court made
additional conforming redactions for consistency. Consistent with Chief Special Master
Brian H. Corcoran’s February 1, 2023 Order, the Opinion refers to petitioner by the
initials “K.A.”
compensation, finding that petitioner had not shown, by a preponderance of the
evidence, that he was entitled to compensation. Subsequently, petitioner filed a Motion
for Review of the Chief Special Master’s decision denying his claim pursuant to Rule 23
and Rule 24 of the Vaccine Rules of the United States Court of Federal Claims (2021)
(Vaccine Rules) in the United States Court of Federal Claims.

                              FINDINGS OF FACT
        On August 12, 2013, petitioner, a medical researcher, received the Tdap vaccine,
when he was fifty-one years old. Prior to receiving the vaccine, petitioner had a medical
history of high cholesterol, hypertension, and a chronic leg condition. Following his
vaccination, on September 1, 2013, petitioner was admitted to the North Shore
University Hospital Emergency Department in Manhasset, New York and petitioner
reported that he had experienced three days of flu-like symptoms, including dry cough,
chills, and swelling of his throat. The medical professionals treating petitioner noted that
he appeared neurologically sound and was not in distress, although they observed
petitioner displaying many common symptoms of an upper respiratory infection or
influenza like illness (URI/ILI), including fever, chills, weakness, nasal discharge,
congestion, dyspnea, and cough. Petitioner was discharged the following day on
September 2, 2013, and petitioner maintains that he continued to experience a fever
through September 3, 2013.
       On September 4, 2013, petitioner was discovered in his driveway complaining of
numbness on his left side, and was transported via ambulance to the emergency
department at St. Francis Hospital in Roslyn, New York. Emergency responders noted
that petitioner walked with an “unsteady gait” and that he had been treated for flu-like
symptoms recently. The same day, September 4, 2013, petitioner was admitted to St.
Francis Hospital for further evaluation. Medical records from petitioner’s September 4,
2013 visit to St. Francis Hospital indicate that petitioner stated
       [t]he current episode started in the past 7 days. The problem occurs
       intermittently. The problem has been unchanged. Associated symptoms
       include weakness. Pertinent negatives include no numbness. Nothing
       aggravates the symptoms. He has tried nothing for the symptoms.
       [P]atient presents to the emergency department for evaluation of
       weakness of the left arm leg and face. Patient states symptoms are [sic]
       originally began approximately 5 days ago when he was attempting to
       climb a hill and noticed weakness in the left leg. Patient then states that he
       developed incoordination of the left face when attempting to brush his
       teeth this morning. Patient denies loss of sensation however states he has
       a tingling sensation diffusely over the left side of his body. There are no
       specific modifying factors. Severity of symptoms mild to moderate.

(alterations added). With regard to his neurological symptoms, petitioner’s admitting
physician Dr. Subash Viswanathan reported that petitioner was “unable to forcefully

                                             2
closed [sic] left eye. Left face shows mild weakness. Otherwise cranial nerves 2-12
intact. There is subjective weakness of the left arm and left leg. However patient is able
to move both extremities with good strength. There is no sensory deficit.” (alteration
added). Dr. Viswanathan also noted
      Pt [patient] had the “flu” 2 weeks ago, not receiving abx [antibiotics].
      Denies recent travel or diarrhea. Was an URI. The past week first noted
      left leg weakness while climbing. Had presented to NSUH [North Shore
      University Hospital], where he works doing bench research on HIV
      [Human Immunodeficiency Virus] nephropathy, where he was admitted.
      CT [Computed tomography] chest was negative. After discharge he has
      been noting a weakness and numbness of the left face/arm/leg. He denies
      any vision change but there is some burning sensation in the left eye. He
      noted toothpaste dripping from the left mouth while brushing his teeth. He
      also complains of bloating and unable to make a BM. His BP [blood
      pressure] has been high.
(alterations added). CT scans of petitioner’s brain and chest did not yield any significant
abnormalities. Lab results indicated, however, that petitioner had the antibodies for the
West Nile Virus, which indicated that he had contracted West Nile Virus at some point in
the past.
        On September 4, 2013, Dr. Michael Han, another treating physician, indicated
“[m]uch of his [petitioner’s] symptoms and findings are non-specific, though bifacial
weakness is most prominent and perhaps most helpful in narrowing down differential. A
major consideration would be AIDP [Acute Inflammatory Demyelinating
Polyneuropathy]/GBS (Guillan [sic] Barre Syndrome) with all the above features,
including potential autonomic dysfunction.” (alterations added). Dr. Han also indicated
that petitioner had suffered a “recent URI [upper respiratory infection] 2 weeks ago.”
(alteration added). During his stay at St. Francis Hospital, petitioner complained
primarily of weakness. Petitioner also reported to Dr. Han that he had experienced flu
like symptoms two weeks prior, and that he developed left leg weakness and difficulty
climbing over a small hill near his home shortly thereafter.
       On September 5, 2013, Dr. Teresa Deangelis, a neurologist, examined petitioner
and reported that “[a] major consideration would be AIDP/GBS (Guillain Barre
Syndrome).” Dr. Deangelis likewise noted that petitioner had experienced “recent URI 2
weeks ago.” Dr. Deangelis’ treatment notes indicate that she started petitioner on a five-
day course of intravenous immunoglobulin therapy on September 5, 2013, which is a
blood product used to treat patients with antibody deficiencies, including neurological
disorders such as Guillain-Barré syndrome. On September 6, 2013, petitioner went
through a rheumatology consult with Dr. William Given, who indicated that petitioner
“states that he was well until about 2 weeks ago when he developed NP [nonproductive]
cough, pharyngitis, malaise, and elevated temperature.” (alteration added). Dr. Given

                                            3
reported that it appeared that petitioner “developed weakness and paresthesias[2]
following what appears to be a viral illness a couple of weeks ago.” (alteration added).
On the same day, September 6, 2013, petitioner had an infectious disease consult with
Dr. Dava Klirsfield. Dr. Klirsfield’s assessment indicated: “Patient with bell’s palsy, left
sided weakness and hyporeflexic, recent tetanus shot and flu-like illness, imaging
shows a dermoid in occipital bone on right, suspect a demyelinating disorder[3] possibly
post viral or post vaccine.” (alteration added). Dr. Klirsfield’s assessment also indicated
that petitioner’s positive West Nile Virus antibodies test had “unclear significance,” and
ordered additional laboratory testing. On September 10, 2013, following two consistent
lumbar punctures, Dr. Doina Glodan diagnosed petitioner with “Guillain-Barre syndrome
post recent viral URI.” Petitioner remained at St. Francis Hospital until September 17,
2013, at which time he was discharged to Glen Cove Hospital, a rehabilitation facility in
Glen Cove, New York. Petitioner’s medical records from his date of discharge indicate
that petitioner stated that he “[f]eels like he is getting better. No new complaints.” While
at Glen Cove Hospital, petitioner received physical therapy, occupational therapy, and
commenced a speech therapy program.
       On September 22, 2013, petitioner’s medical records indicate that “he developed
acute right facial weakness with right hemiparesis, and CAT scan of the head revealed
no new acute pathology, and the patient after contacting primary neurology was
transferred to North Shore University Hospital for further investigation and treatment.”
Treatment notes from North Shore University Hospital state that petitioner displayed
increased lethargy, weakness, and right sided numbness and tingling that started two to
three days prior, with trace reflexes and worsened right-side issues. Petitioner’s
admittance documents from North Shore University Hospital indicate that he was
experiencing “new onset of R [right] side numbness/tingling weakness in the setting of
recently diagnosed of [sic] AIDP.” (alterations added).
        On September 24, 2013, petitioner began plasmapheresis treatment.4
Petitioner’s treatment notes state that, as a result of the plasmapheresis treatment,
petitioner exhibited “significant improvement” in strength and respiration. According to

2Paresthesias is defined as “tingling or pricking (‘pins and needles’), caused chiefly by
pressure on or damage to peripheral nerves.” Encyclopedia of Virology 738 (Dennis H.
Bamford & Mark Zuckerman eds., 4th ed. 2021).
3  “A demyelinating disorder is any condition that causes damage to the protective
covering (myelin sheath) that surrounds nerve fibers in your brain, the nerves leading to
the eyes (optic nerves) and spinal cord.” Demyelinating disease: What can you do about
it?,     MAYO       CLINIC,     https://www.mayoclinic.org/diseases-conditions/multiple-
sclerosis/expert-answers/demyelinating-disease/faq-20058521 (last visited Feb. 10,
2023).
4 Plasmapheresis “is a nonsurgical therapy that removes and replaces a patient’s blood
plasma.”       Plasmapheresis        Program,      UC     SAN      DIEGO      HEALTH,
https://health.ucsd.edu/specialties/apheresis/pages/plasmapheresis.aspx (last visited
Feb. 10, 2023).
                                             4
petitioner’s medical records, thereafter, on September 26, 2013, petitioner saw a
dietician who indicated in petitioner’s medical history that petitioner had initially
presented “with progressive weakness post tetanus shot 8 weeks ago.” The dietician
also noted that petitioner had reported that “he kept losing weight since after his tetanus
shot despite adequate intake.” On October 8, 2013, petitioner was discharged from
North Shore University Hospital and returned to Glen Cove Hospital for further
rehabilitation, where he stayed until October 21, 2013.
        On October 21, 2013, petitioner was “discharged home with supervision from
friends and family with a follow up with Dr. Han.” Petitioner had an initial evaluation at
Transitions Rehabilitation on October 23, 2013, when he stated that he was in “good
health until September of this year.” The following day, on October 24, 2013, petitioner
was hospitalized at North Shore University Hospital after he was “FOUND LYING ON
FLOOR AOX3 -LOC C/O SEVERE HEAD ACHE 10/10 PAIN SCALE, PT WAS JUST
RELEASED MONDAY FROM REHAB FOR A NEUROLOGICAL REACTION TO A
TETNUS SHOT 2 MONTHS AGO AND STARTED GETTING HEAD ACHE TONIGHT.”
(capitalization in original). Petitioner’s medical records from North Shore University
Hospital, dated October 24, 2013, indicate that he was “violently vomiting” and was
experiencing “generalized weakness.” A CT scan from the North Shore University
Hospital Emergency Department of petitioner’s head showed a “6 mm left extra-axial
collection with mass effect, no shift. Denies any photophobia, vision loss, neck pain,
increased weakness, fever/chills.” On October 25, 2013, petitioner underwent a
magnetic resonance imaging (MRI) scan of petitioner’s brain, which revealed “[s]mall
bilateral subacute subdural hematomas with diffuse dural enhancement,” which “raise
the possibility of intracranial hypotension.” Petitioner also received a blood patch for
suspected spinal tap CSF leak.5 On October 27, 2013, petitioner underwent a repeat
head CT scan, which revealed an interval increase in size in the left subdural
hematoma. Petitioner was started on Dialudid and his previously prescribed Neurontin
dose was increased. Neurosurgery advised that no intervention was necessary.
Petitioner continued to follow up with Dr. Han through the end of 2013, and Dr. Han
reported petitioner’s overall improvement.
        Petitioner did not visit Dr. Han again until September 2, 2014, at which time
petitioner reported that he was still experiencing painful paresthesias in his feet, but no
longer required a cane to walk. Petitioner also reported that “[h]is balance is still a bit off
though he feels that he is 99% back to normal.” Dr. Han advised petitioner to continue
on his then-current course of medication and to see Dr. Han again in 4-6 months.
Petitioner saw Dr. Han on November 24, 2015 and Dr. Han’s treatment notes from the
November 24, 2015 visit state that petitioner continued to experience “paresthesias,”
and Dr. Han theorized that “this still could be residual from Guillain-Barre,” but that “we
should not ignore the possibility of another neuropathic process such as diabetes or

5 A cerebrospinal fluid (CSF) leak occurs when there is a hole or tear in the outermost
layer of the membranes surrounding the brain and spinal cord, which allows the fluid to
escape.      CSF       Leak     (Cerebrospinal     fluid   leak),     MAYO       CLINIC,
https://www.mayoclinic.org/diseases-conditions/csf-leak/symptoms-causes/syc-
20522246 (last visited Feb. 10, 2023).
                                              5
borderline diabetes.” Dr. Han ordered an electromyography (EMG) procedure and
advised petitioner to continue with his previously prescribed Neurotonin. On December
4, 2015, petitioner underwent an EMG that “did not demonstrate the concern for
possible axonal of demyelinating polyneuropathy.” Dr. Han ordered an “MRI
lumbosacral spine to rule out a significant herniated disc with nerve root compression,”
which petitioner went through on December 4, 2015.
       On May 20, 2016, petitioner had an appointment with Dr. Adam Criss for
“reevaluation of Guillain-Barre syndrome.” Treatment notes indicate that petitioner
“continues to do well although still has neuropathic pains associated with this syndrome.
He’ll continue with Neurontin 600/300/300. Weight loss and increased physical activity
was encouraged. I will see him back in 6 months.”
Procedural History
        On August 11, 2016, petitioner filed a petition seeking compensation under the
Vaccine Act, 42 U.S.C. § 300aa-11(c)(1)(C)(ii), alleging that the August 12, 2013 Tdap
vaccination more likely than not caused his GBS, with the onset of the injury taking
place on or about August 21, 2013. Special Master Mindy M. Roth was the Special
Master initially assigned to petitioner’s case. During the pendency of petitioner’s case,
he filed his medical records in nineteen exhibits and submitted two declarations. On
February 23, 2017, respondent filed its Rule 4(c) report, pursuant to the Vaccine Rules,
opposing compensation because “the medical records alone do not provide
preponderant proof of a vaccine-related injury, and petitioner has not provided a reliable
expert report in support of his claim.” In addition, respondent stated that “the records
also reflect that petitioner’s treating physicians were immediately concerned that his
symptoms were indicative of ‘Guillain-Barre syndrome post recent viral URI.’”
Respondent also argued that “petitioner has failed to rule out other potential causes for
his injury. Petitioner had positive test results for both CMV [cytomegalovirus] and EBV
[Epstein-Barr virus] infections, two known antecedents associated with GBS.”
(alterations added).
        On March 22, 2017, Special Master Roth held a status conference with the
parties, after which petitioner filed additional medical records and his first expert report
authored by neurologist-immunologist Dr. Lawrence Steinman on August 4, 2017 in
support of petitioner’s case. On December 4, 2017, respondent filed its first expert
report authored by immunologist Kathleen Collins, M.D., Ph.D. In her expert report, Dr.
Collins stated that “the medical record better supported the conclusion that Petitioner’s
GBS was attributable to the ‘influenza-like illness’ that he appeared to have experienced
in the interval between his vaccination and onset of neurologic symptoms.” On February
20, 2018, petitioner filed Dr. Steinman’s second expert report, in which Dr. Steinman
characterized “Dr. Collins’s ILI terminology as imprecise.” On June 13, 2018,
respondent filed Dr. Collins’ second expert report and first response to Dr. Steinman’s
expert report. On December 28, 2018, petitioner filed Dr. Steinman’s third expert report,
which “‘repeated his prior challenge to Dr. Collins’s use of ILI.” On May 7, 2019,
respondent filed Dr. Collins’ third expert report, in which Dr. Collins defended her theory
of ILI as the more likely the cause of petitioner’s GBS. On July 29, 2019, Special Master
Roth held a status conference to discuss petitioner’s aluminum adjuvant causation

                                             6
theory. During the status conference, respondent expressed the implausibility of
petitioner’s aluminum adjuvant theory and Special Master Roth allowed petitioner to file
and assert a new causation theory of molecular mimicry. On October 7, 2019, petitioner
filed Dr. Steinman’s fourth expert report, wherein Dr. Steinman proffered, for the first
time, molecular mimicry as a new causation theory, which he contended co-existed with
his prior aluminum adjuvant theory. As explained in the Chief Special Master’s
Entitlement Decision:
         Specifically, he [Dr. Steinman] (a) attempted to propose the degree of
         amino acid homology that would be necessary, arguing that five (and
         perhaps even four) out of a twelve amino acid string is sufficient (b)
         performed “BLAST”[6] searches with an online government database for
         the antigenic components of the Tdap vaccine, in order to identify the
         amino acids comprising them, and (c) compared them to identified GBS
         targets.
(internal references omitted; alterations added). Thereafter, respondent filed Dr. Collins’
fourth, and final, expert report on January 23, 2020.
       More than three years and seven months after petitioner filed his petition for
compensation under the Vaccine Act, and following four expert reports filed by petitioner
and four expert reports filed by respondent, on March 23, 2020, petitioner asked to
retain an infectious disease expert in order to file another expert report, in addition to
the expert reports previously filed by Dr. Steinman. Then on May 22, 2020, petitioner
filed a formal motion for leave to file an expert report from an infectious disease
specialist as well as an expert report from a specialist in biostatistics. Petitioner stated:
         Respondent’s primary and persistent defense to petitioner’s claim that the
         Tdap vaccine caused his Guillain Barré syndrome (“GBS”) is the argument
         that petitioner had viral symptoms after his vaccination. Respondent
         argued in his Rule 4(c) Report that petitioner’s symptoms “were indicative
         of ‘Guillain-Barre syndrome post recent viral URI.” [sic] Respondent
         presents several citations to the medical record purporting to support his
         argument. Respondent also argues in his Rule 4(c) Report that “petitioner
         has failed to rule out other potential caused [sic] for his injury. Petitioner
         had positive test results for both CMV [Cytomegalovirus] and EVC [Ellis-
         van Creveld] infections, two known antecedents associated with GBS.”

6   As explained in a footnote to the Chief Special Master’s Entitlement Decision:
         Basic Local Alignment Search Tool (“BLAST”) is a medical/scientific
         internet resource that assists researchers in finding regions of similarity
         between biological sequences of amino acids. The program compares
         nucleotide or protein sequences to sequence databases and calculates
         the statistical significance. BLAST, U.S. National Library of Medicine,
         https://blast.ncbi.nlm.nih.gov/Blast.cgi

                                               7
(internal citations omitted; alteration added). Petitioner argued that respondent had
previously “filed four expert reports from an expert in infectious disease,” that pointed to
an “influenza-like illness” as an “alternative cause” for petitioner’s GBS. According to
petitioner,
       [b]ecause the controversy in this case focuses in large part on
       respondent’s claim that an infectious disease caused [K.A.]’s GBS and
       because respondent has relied on the opinion of a specialist in infectious
       disease, petitioner submits that it is appropriate for petitioner to file an
       expert report from a specialist in infectious disease.
(alterations added).
       On June 12, 2020, Special Master Roth issued an Order which, in relevant part,
denied petitioner’s motion for file to file both the additional requested expert report from
an infectious disease expert, as well as from a biostatistics expert. The text of Special
Master Roth’s Order stated:
       On May 22, 2020, petitioner filed a Motion for Leave to file an expert
       report from an infectious disease specialist and an expert report from a
       specialist in biostatistics. See ECF No. 71. Petitioner’s Motion is hereby
       DENIED.
       On June 4, 2020, petitioner filed an unopposed Motion for Extension of
       Time until June 22, 2020, to file a supplemental expert report from Dr.
       Steinman. See ECF No. 72. Petitioner’s Motion is hereby GRANTED.
       Petitioner shall file a supplemental expert report from Dr. Steinman by
       Monday, June 22, 2020.
       A status conference will be scheduled following the submission of Dr.
       Steinman’s supplemental report.
       Based on the foregoing, the following is hereby ORDERED:
       1) Petitioner shall file a supplemental expert report from Dr. Steinman by
       no later than Monday, June 22, 2020.
(capitalization and emphasis in original). Pursuant to Special Master Roth’s Order, on
June 22, 2020, petitioner filed Dr. Steinman’s fifth, and final, expert report.
       On January 27, 2021, the case was reassigned to Chief Special Master
Corcoran. On April 26, 2021, petitioner renewed his request for leave to file expert
reports from specialists in infectious disease and biostatistics, which request had been
denied previously by Special Master Roth. Chief Special Master Corcoran issued an
Order on April 27, 2021 directing petitioner to file his motion for a ruling on the record by
June 29, 2021. On July 2, 2021, petitioner filed his motion for a ruling on the record in
support of his entitlement to compensation under the Vaccine Act and his motion for
leave to file additional expert reports from experts in infectious disease and biostatistics.
On September 13, 2021, respondent filed its response to petitioner’s motion for ruling
on the record. On October 12, 2021, petitioner filed a reply brief which included a
footnote which stated that “petitioner acknowledges the Court’s authority to decide this

                                             8
case without an evidentiary hearing during which the experts’ presentations can be
explored, in the context of the present case, where petitioner’s theory is closely
contested, a hearing would supply valuable elaboration of petitioner’s case and a
hearing should be conducted.” Prior to issuing his Entitlement Decision, Chief Special
Master Corcoran did not issue orders addressing petitioner’s request for an evidentiary
hearing or to allow petitioner to present additional experts.
        On April 18, 2022, Chief Special Master Corcoran issued his Entitlement
Decision in which he denied petitioner’s claims in full. The Chief Special Master stated
that petitioner had not established that he met the requirements to receive
compensation based on the test in Althen v. Secretary of Health & Human Services,
418 F.3d 1274 (Fed. Cir. 2005).7 Regarding the first prong of the Althen test, the
medical theory causally connecting the vaccination and the injury, id. at 1278, the Chief
Special Master noted: “Two causation theories were ultimately advanced in this case,
but neither was preponderantly established.” The Chief Special Master indicated that
“[i]t was wise of Petitioner to “supplement” his case with a second causation theory, for
the first one Dr. Steinman proposed—that alum included in the Tdap vaccine as an
adjuvant can produce demyelination—was woefully inadequate,” noting in a footnote,
“[i]ndeed, Petitioner largely seems to have walked away from his first theory by the time
of his reply brief.” The Chief Special Master determined that “individual components of
the [aluminum adjuvant] theory, as reliably established as they were, were not
persuasively connected to other preponderant evidence to establish that the Tdap
vaccine likely can cause GBS solely on the basis of the inclusion of the aluminum
adjuvant.” (emphasis in original; alteration added). Regarding petitioner’s second
causation theory, molecular mimicry, Chief Special Master Corcoran explained:
      Petitioner’s second theory was one that, more often than not in Program
      cases, is the primary theory offered to explain how virtually any vaccine
      could produce an autoimmune disease—via molecular mimicry. But not
      only was it proposed late in the game, but it too was not preponderantly
      shown to be likely causal. All Dr. Steinman did was offer evidence
      suggesting a theoretic possibility of homology between Tdap vaccine
      components and locations in the nerve structures where an autoimmune
      attack might occur. But this is a relatively easy showing to make, given the
      prevalence of homology in nature. It does not amount to a showing that a

7 As described below, the United States Court of Appeals for the Federal Circuit in
Althen explained:

      Concisely stated, Althen’s burden is to show by preponderant evidence
      that the vaccination brought about her injury by providing: (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 v. Sec’y of Health & Hum. Servs., 418 F.3d at 1278.

                                           9
       cross-reaction instigated by the Tdap vaccine resulting in GBS is “more
       likely than not.” And Dr. Collins offered evidence and testimony raising
       reasonable questions about whether every variant of GBS inherently
       unfolds only from molecular mimicry causing the production of cross-
       reactive autoantibodies, or only at the identified myelin targets.
(emphasis in original). Therefore, for the first Althen prong, the Chief Special Master
concluded that “neither of the causation theories offered was preponderantly
established with sufficient reliable medical or scientific evidence, despite Dr. Steinman’s
ample credentials to opine on the subject.”
        Regarding the second Althen prong, the logical sequence of cause and effect
showing that the vaccination was the reason for the injury, id., the Chief Special Master
indicated that “[s]everal items of record evidence weigh against Petitioner’s assertion
that the Tdap vaccine he received likely ‘did cause’ his GBS. In particular, the majority
of immediate treaters did not propose vaccination to be causal, finding far more
significant the indisputable evidence of an intercurrent URI,” and, furthermore, “the
record reveals several instances in which treaters proposed that Petitioner’s URI did
play a role in his subsequent neurologic injury.” (emphasis in original). The Chief
Special Master concluded: “Overall, the medical records strongly support the conclusion
that Petitioner’s intercurrent URI likely caused his GBS—not that it was caused by the
Tdap vaccine.” Therefore, the Chief Special Master determined
       [p]etitioner has not preponderantly established that the Tdap vaccine can
       cause GBS, under either of the two causation theories ventured over the
       case’s six-year life—and even if he had, the record demonstrates it is far
       more likely his GBS was attributable to an intercurrent upper respiratory
       infection (“URI”) than vaccination.
        Regarding the third Althen prong, the showing of a proximate temporal
relationship between vaccination and injury, id., Chief Special Master Corcoran noted
that “Petitioner’s success in establishing that the timeframe for his onset of symptoms
post-vaccination was medically acceptable (in terms of vaccine causation) is not
consistent from theory to theory,” and concluded that “because the claim fails on the
first two Althen prongs, Petitioner’s ability to preponderantly support the third prong
does not avail him.”
       Chief Special Master Corcoran also indicated in the Entitlement Decision that an
evidentiary hearing was not necessary and that “[t]he case was appropriately decided
on the papers.” In his Entitlement Decision, the Chief Special Master indicated that the
parties had previously filed numerous expert reports, which Chief Special Master
Corcoran characterized as a “back-and-forth between Drs. Steinman and Collins over
Petitioner’s initial causation theory.” Chief Special Master Corcoran also stated:
       Notably (and after the case had existed for nearly three years), it was
       discussed during a July 2019 status conference (perhaps in reaction to
       questions about whether the case was likely to settle) that Respondent
       deemed Petitioner’s causation theory implausible—prompting the special
       master formerly presiding over the case to order a deadline for Petitioner

                                            10
       to file a new report, but this time “modifying” the theory to allege molecular
       mimicry as the causal mechanism. Scheduling Order, dated July 19, 2019
       (ECF No. 59). Dr. Steinman did so by that fall, and another, shorter round
       of expert report filings occurred, with the final report (from Dr. Steinman)
       filed in June 2020.
       On May 18, 2022, after Chief Special Master Corcoran issued his Entitlement
Decision petitioner timely filed a Motion for Review of the Chief Special Master’s
Entitlement Decision in the United States Court of Federal Claims, in which petitioner
puts forth three numbered objections:
       Numbered Objection One
       1. Denial of Petitioner’s repeated requests to retain an infectious disease
       expert resulted in an unbalanced review of Petitioner’s presentation of
       Althen Prong 2 and constituted an abuse of discretion under the
       circumstances of this case.
       Numbered Objection Two
       2. In the case at bar, the Chief Special Master failed to recognize that the
       posited medical theory of molecular mimicry went well beyond the mere
       identification of homologies[8] between components of the Tdap vaccine
       and self-antigen such as human myelin protein, leading to GBS (Dec. at
       40). The court’s misconstruction of the record and incorrect application of
       the law requires vacatur of the Decision. The court compounded its error
       by holding that Petitioner’s causal medical theory was “undercut” by
       epidemiological evidence as to causation for which an expert was denied
       to Petitioner despite repeated requests throughout the case (Dec. at 40-
       41).
       Numbered Objection Three
       3. While Petitioner argued in the course of his Motion for Ruling on the
       Record that he had carried the burden of proof preponderantly for each
       prong of Althen, including prong 1, the court misinterpreted the law in
       rejecting an alternative argument that, in light of recent case law, Althen
       prong 1 could be properly established by a biologically plausible
       evidentiary showing founded upon a sound and reliable medical or
       scientific explanation.
(capitalization and emphasis in original; alteration added).

8 A “homology” is an antigenic similarity “between the vaccine’s component and self
neurologic structures.” See Caredio v. Sec’y of Health & Hum. Servs., No. 17-79V, 2021
WL 4100294, at *13 (Fed. Cl. Spec. Mstr. July 30, 2021), review denied, No. 17-79V,
2021 WL 6058835 (Fed. Cl. Dec. 3, 2021). In Caredio, Dr. Steinman, who offered expert
testimony for the Caredio petitioner, “admitted that demonstrating a theoretical basis for
homology is only the first step to establishing a possible causal association.” Id.
                                            11
      On June 16, 2022, respondent filed its response to petitioner’s Motion for
Review, in which respondent argues that
      [b]ecause petitioner had a full and fair opportunity to present his case,
      including filing five expert reports over three years addressing the ILI/URI
      issue in the case and modifying his causation theory, the Chief Special
      Master appropriately decided this case on the existing record, as further
      input from an infectious disease expert for petitioner was neither required
      nor warranted.
Respondent also argues that “[t]he Chief Special Master properly applied the law,
including Torday [v. Secretary of Health & Human Services, No. 07-372V, 2009 WL
5196163 (Fed. Cl. Spec. Mstr. Dec. 10, 2009)], and acted within his discretion in
deciding this case without a hearing.” (alteration added). In its response, respondent
asserts that the Chief Special Master considered the appropriate and relevant evidence,
“and stated a rational basis in concluding that petitioner failed to demonstrate how the
Tdap vaccine can cause GBS via molecular mimicry under Althen prong 1.” Finally,
respondent argues that the Chief Special Master applied the correct evidentiary
standard in evaluating whether petitioner preponderantly met the Althen prong 1, and
that the “Federal Circuit precedent requires a petitioner to present more than a
‘plausible theory’ of vaccine causation.” After the Motion for Review was fully briefed,
this court held oral argument.
                                     DISCUSSION
       When reviewing a Special Master’s decision, the assigned Judge of the United
States Court of Federal Claims shall:
      (A) uphold the findings of fact and conclusions of law of the special master
      and sustain the special master’s decision,
      (B) set aside any findings of fact or conclusion of law of the special master
      found to be arbitrary, capricious, an abuse of discretion, or otherwise not
      in accordance with law and issue its own findings of fact and conclusions
      of law, or
      (C) remand the petition [filed under § 300aa-11] to the special master for
      further action in accordance with the court's direction.

Munn v. Sec’y of Health & Hum. Servs., 970 F.2d 863, 867 (Fed. Cir. 1992) (alteration
in original); see also 42 U.S.C. § 300aa-12(e)(2) (2018). The legislative history of the
Vaccine Act states: “The conferees have provided for a limited standard for appeal from
the [special] master’s decision and do not intend that this procedure be used frequently,
but rather in those cases in which a truly arbitrary decision has been made.” H.R. Conf.
Rep. No. 101-386, at 516–17, reprinted in 1989 U.S.C.C.A.N. 3018, 3120 (alteration
added).

       In Markovich v. Secretary of Health & Human Services, the United States Court
of Appeals for the Federal Circuit wrote, “[u]nder the Vaccine Act, the Court of Federal
Claims reviews the Chief Special Master’s decision to determine if it is ‘arbitrary,
capricious, an abuse of discretion, or otherwise not in accordance with the law.’ 42
                                           12
U.S.C. § 300aa-12(e)(2)(B).” Markovich v. Sec’y of Health & Hum. Servs., 477 F.3d
1353, 1355–56 (Fed. Cir.), cert. denied, 552 U.S. 816 (2007); see also Kirby v. Sec’y of
Health & Hum. Servs., 997 F.3d 1378, 1381 (Fed. Cir. 2021); Sharpe v. Sec’y of Health
& Hum. Servs., 964 F.3d 1072, 1077 (Fed. Cir. 2020) (“This court thus performs the
same task as the Court of Federal Claims and reviews the special master’s legal
determinations de novo, fact findings under an arbitrary and capricious standard, and
discretionary rulings for an abuse of discretion.” (citing Munn v. Sec’y of Health & Hum.
Servs., 970 F.2d at 870-73, 870 n.10)); see also K.G. v. Sec’y of Health & Hum. Servs.,
951 F.3d 1374, 1379 (Fed. Cir. 2020); Oliver v. Sec’y of Health & Hum. Servs., 900 F.3d
1357, 1360 (Fed. Cir. 2018) (citing Milik v. Sec’y of Health & Hum. Servs., 822 F.3d
1367, 1375–76 (Fed. Cir. 2016)); Deribeaux ex rel. Deribeaux v. Sec’y of Health & Hum.
Servs., 717 F.3d 1363, 1366 (Fed. Cir.), reh’g and reh’g en banc denied (Fed. Cir.
2013) (The United States Court of Appeals for the Federal Circuit stated that “we
‘perform[ ] the same task as the Court of Federal Claims and determine[ ] anew whether
the special master’s findings were arbitrary or capricious.’” (alterations in original)
(quoting Lampe v. Sec’y of Health & Hum. Servs., 219 F.3d 1357, 1360 (Fed. Cir.
2000))); W.C. v. Sec’y of Health & Hum. Servs., 704 F.3d 1352, 1355 (Fed. Cir. 2013);
Hibbard v. Sec’y of Health & Hum. Servs., 698 F.3d 1355, 1363 (Fed. Cir. 2012); de
Bazan v. Sec’y of Health & Hum. Servs., 539 F.3d 1347, 1350 (Fed. Cir. 2008); Avera v.
Sec’y of Health & Hum. Servs., 515 F.3d 1343, 1347 (Fed. Cir.) (“Under the Vaccine
Act, we review a decision of the special master under the same standard as the Court of
Federal Claims and determine if it is ‘arbitrary, capricious, an abuse of discretion, or
otherwise not in accordance with law.’” (quoting 42 U.S.C. § 300aa-12(e)(2)(B))), reh’g
and reh’g en banc denied (Fed. Cir. 2008); Althen v. Sec’y of Health & Hum. Servs., 418
F.3d at 1277; Faup v. Sec’y of Health & Hum. Servs., 147 Fed. Cl. 445, 458 (2019);
Dodd v. Sec’y of Health & Hum. Servs., 114 Fed. Cl. 43, 47 (2013); Taylor v. Sec’y of
Health & Hum. Servs., 108 Fed. Cl. 807, 817 (2013). The abuse of discretion standard
is applicable when the special master excludes evidence or limits the record upon which
he or she relies. See Munn v. Sec’y of Health & Hum. Servs., 970 F.2d at 870. The
United States Court of Appeals for the Federal Circuit has indicated that:

      These standards vary in application as well as degree of deference. Each
      standard applies to a different aspect of the judgment. Fact findings are
      reviewed by us, as by the Claims Court judge, under the arbitrary and
      capricious standard; legal questions under the “not in accordance with
      law” standard; and discretionary rulings under the abuse of discretion
      standard. The latter will rarely come into play except where the special
      master excludes evidence.
Id. at 871 n.10; see also Kirby v. Sec’y of Health & Hum. Servs., 997 F.3d at 1381 (“We
do not reweigh the factual evidence, assess whether the special master correctly
evaluated the evidence, or examine the probative value of the evidence or the credibility
of the witnesses—these are all matters within the purview of the fact finder” (citing
Porter v. Sec’y of Health & Hum. Servs., 663 F.3d 1242, 1249 (Fed. Cir. 2011)));
Carson ex rel. Carson v. Sec’y of Health & Hum. Servs., 727 F.3d 1365, 1369 (Fed. Cir.
2013); Deribeaux ex rel. Deribeaux v. Sec’y of Health & Hum. Servs., 717 F.3d at 1366;
W.C. v. Sec’y of Health & Hum. Servs., 704 F.3d at 1355; Griglock v. Sec’y of Health &

                                           13
Hum. Servs., 687 F.3d 1371, 1374 (Fed. Cir. 2012); Porter v. Sec’y of Health & Hum.
Servs., 663 F.3d at 1249 (explaining that the reviewing court “do[es] not reweigh the
factual evidence, assess whether the special master correctly evaluated the evidence,
or examine the probative value of the evidence or the credibility of the witnesses—these
are all matters within the purview of the fact finder” (citing Broekelschen v. Sec’y of
Health & Hum. Servs., 618 F.3d 1339, 1345 (Fed. Cir. 2010)), reh’g and reh’g en banc
denied (Fed. Cir. 2012); Dodd v. Sec’y of Health & Hum. Servs., 114 Fed. Cl. at 56.
“[T]he special masters have broad discretion to weigh evidence and make factual
determinations.” Dougherty v. Sec’y of Health & Hum. Servs., 141 Fed. Cl. 223, 229
(2018). As explained by the Federal Circuit:

       With regard to both fact-findings and fact-based conclusions, the key
       decision maker in the first instance is the special master. The Claims
       Court owes these findings and conclusions by the special master great
       deference—no change may be made absent first a determination that the
       special master was “arbitrary and capricious.”
Munn v. Sec’y of Health & Hum. Servs., 970 F.2d at 870; see also 42 U.S.C. § 300aa-
12(e)(2)(B).

        “‘[R]eversible error is extremely difficult to demonstrate if the special master has
considered the relevant evidence of record, drawn plausible inferences and articulated a
rational basis for the decision.’” Kirby v. Sec’y of Health & Hum. Servs., 997 F.3d at
1381 (quoting Lampe v. Sec’y of Health & Hum. Servs., 219 F.3d at 1360); see also
Hibbard v. Sec’y of Health & Hum. Servs., 698 F.3d at 1363 (“[I]f the special master ‘has
considered the relevant evidence of record, drawn plausible inferences and articulated a
rational basis for the decision, reversible error will be extremely difficult to
demonstrate.’” (quoting Hines v. Sec’y of Health & Hum. Servs., 940 F.2d 1518, 1528
(Fed. Cir. 1991))); Porter v. Sec’y of Health & Hum. Servs., 663 F.3d at 1253–54;
Lampe v. Sec’y of Health & Hum. Servs., 219 F.3d at 1360; Avila ex rel. Avila v. Sec’y
of Health & Hum. Servs., 90 Fed. Cl. 590, 594 (2009); Dixon v. Sec’y of Health & Hum.
Servs., 61 Fed. Cl. 1, 8 (2004) (“The court’s inquiry in this regard must therefore focus
on whether the Special Master examined the ‘relevant data’ and articulated a
‘satisfactory explanation for its action including a rational connection between the facts
found and the choice made.’” (quoting Motor Vehicle Mfrs. Association v. State Farm
Mut. Auto. Ins. Co., 463 U.S. 29, 43 (1983) (quoting Burlington Truck Lines, Inc. v.
United States, 371 U.S. 156, 168 (1962)))).

       As noted by the United States Court of Appeals for the Federal Circuit:

       Congress assigned to a group of specialists, the Special Masters within
       the Court of Federal Claims, the unenviable job of sorting through these
       painful cases and, based upon their accumulated expertise in the field,
       judging the merits of the individual claims. The statute makes clear that,
       on review, the Court of Federal Claims is not to second guess the Special
       Masters [sic] fact-intensive conclusions; the standard of review is uniquely
       deferential for what is essentially a judicial process. Our cases make clear

                                            14
       that, on our review we remain equally deferential. That level of deference
       is especially apt in a case in which the medical evidence of causation is in
       dispute.
Deribeaux ex rel. Deribeaux v. Sec’y of Health & Hum. Servs., 717 F.3d at 1366–67
(alterations in original) (quoting Hodges v. Sec’y of Health & Hum. Servs., 9 F.3d 958,
961 (Fed. Cir. 1993)); Hibbard v. Sec’y of Health & Hum. Servs., 698 F.3d at 1363;
Locane v. Sec’y of Health & Hum. Servs., 685 F.3d 1375, 1380 (Fed. Cir. 2012). The
United States Court of Appeals for the Federal Circuit has explained that the reviewing
courts “‘do not sit to reweigh the evidence. [If] the special master's conclusion [is] based
on evidence in the record that [is] not wholly implausible, we are compelled to uphold
that finding as not being arbitrary and capricious.’“ Deribeaux ex rel. Deribeaux v. Sec’y
of Health & Hum. Servs., 717 F.3d at 1367 (modification in original) (quoting Lampe v.
Sec’y of Health & Hum. Servs., 219 F.3d at 1363); see also K.G. v. Sec’y of Health &
Hum. Servs., 951 F.3d at 1379 (“With respect to factual findings, however, we will
uphold the special master’s findings of fact unless they are clearly erroneous.” (citing
Althen v. Sec’y of Health & Hum. Servs., 418 F.3d at 1278)); Hibbard v. Sec’y of Health
& Hum. Servs., 698 F.3d at 1363 (citing Cedillo v. Sec’y of Health & Hum. Servs., 617
F.3d 1328, 1338 (Fed. Cir. 2010)).

       The United States Court of Appeals for the Federal Circuit has explained that:
       A petitioner can establish causation in one of two ways. Id. [Broekelschen
       v. Sec’y of Health & Hum. Servs., 618 F.3d at 1341] If the petitioner shows
       that he or she received a vaccination listed on the Vaccine Injury Table, 42
       U.S.C. § 300aa–14, and suffered an injury listed on that table within a
       statutorily prescribed time period, then the Act presumes the vaccination
       caused the injury. Andreu [ex rel. Andreu] v. Sec’y of Health & Hum.
       Servs., 569 F.3d 1367, 1374 (Fed. Cir. 2009). Where, as here, the injury is
       not on the Vaccine Injury Table, the petitioner may seek compensation by
       proving causation-in-fact.

Milik v. Sec’y of Health & Hum. Servs., 822 F.3d at 1379 (alterations added) see also
W.C. v. Sec’y of Health & Hum. Servs., 704 F.3d at 1356; Broekelschen v. Sec’y of
Health & Hum. Servs., 618 F.3d at 1346; Pafford v. Sec’y of Health & Hum. Servs., 451
F.3d 1352, 1356 (Fed. Cir.), reh’g and reh’g en banc denied (Fed. Cir. 2006), cert.
denied, 551 U.S. 1102 (2007); Grant v. Sec’y of Health & Hum. Servs., 956 F.2d 1144,
1147–48 (Fed. Cir. 1992); Faup v. Sec’y of Health & Hum. Servs., 147 Fed. Cl. at 458;
Dodd v. Sec’y of Health & Hum. Servs., 114 Fed. Cl. at 50; Paluck v. Sec’y of Health &
Hum. Servs., 104 Fed. Cl. 457, 467–68 (2012).

        When proving eligibility for compensation for a petition under the Vaccine Act, a
petitioner must establish by a preponderance of the evidence that he received a vaccine
set forth in the Vaccine Injury Table and that injury caused by the vaccination occurred
within the required amount of time. See Althen v. Sec’y of Health & Hum. Servs., 418
F.3d at 1278; see also 42 U.S.C. § 300aa-11(c)(1)(A). Regarding the preponderance of
the evidence standard, the Vaccine Act requires “‘the trier of fact to believe that the
existence of a fact is more probable than its nonexistence before [he] may find in favor

                                            15
of the party who has the burden to persuade the [judge] of the fact's existence.’”
Moberly ex rel. Moberly v. Sec’y of Health and Hum. Servs., 592 F.3d 1315, 1322 n.2
(Fed. Cir. 2010) (alterations in original) (quoting Concrete Pipe & Prods. of Cal., Inc. v.
Constr. Laborers Pension Trust for S. Cal., 508 U.S. 602 (1993)). In demonstrating this
preponderance of evidence, petitioner may not rely on his or her testimony alone to
establish preponderant evidence of vaccine administration. According to the Vaccine
Act, “[t]he special master or court may not make such a finding based on the claims of a
petitioner alone, unsubstantiated by medical records or by medical opinion.” 42 U.S.C.
§ 300aa-13(a)(1).

        In weighing the evidence, the Special Master has discretion to determine the
relative weight of the evidence presented, including contemporaneous medical records
and oral testimony. See Burns v. Sec’y of Health & Hum. Servs., 3 F.3d 415, 417 (Fed.
Cir. 1993) (finding that the Special Master had thoroughly considered evidence in
record, had discretion not to hold an additional evidentiary hearing); see also Hibbard v.
Sec’y of Health & Hum. Servs., 698 F.3d at 1368 (finding it was not arbitrary or
capricious for the Special Master to weigh diagnoses of different treating physicians
against one another, including when their opinions conflict).

      “Clearly it is not then the role of this court to reweigh the factual evidence,
      or to assess whether the special master correctly evaluated the evidence.
      And of course we do not examine the probative value of the evidence or
      the credibility of the witnesses. These are all matters within the purview of
      the fact finder.”

Dodd v. Sec’y of Health & Hum. Servs., 114 Fed. Cl. at 56 (quoting Munn v. Sec’y of
Health & Hum. Servs., 970 F.2d at 870 n.10); see also Broekelschen v. Sec’y of Health
& Hum. Servs., 618 F.3d at 1349; Rich v. Sec’y of Health & Hum. Servs., 129 Fed. Cl.
642, 655 (2016); Paluck v. Sec’y of Health & Hum. Servs., 104 Fed. Cl. at 467 (“So long
as those findings are ‘based on evidence in the record that [is] not wholly implausible,’
they will be accepted by the court.” (quoting Lampe v. Sec’y of Health & Hum. Servs.,
219 F.3d at 1363 (alteration in original))). “Determinations subject to review for abuse of
discretion must be sustained unless ‘manifestly erroneous.’“ Heddens v. Sec’y of Health
& Hum. Servs., 143 Fed. Cl. 193 (2019) (quoting Piscopo v. Sec’y of Health & Hum.
Servs., 66 Fed. Cl. 49, 53 (2005) (citations omitted)).

        Additionally, a Special Master is “not required to discuss every piece of evidence
or testimony in [his or] her decision.” Snyder ex rel. Snyder v. Sec’y of Health & Hum.
Servs., 88 Fed. Cl. 706, 728 (2009) (brackets added). As explained by a Judge of the
United States Court of Federal Claims:

      “[W]hile the special master need not address every snippet of evidence
      adduced in the case, see id. [Doe v. Sec’y of Health & Hum. Servs., 601
      F.3d 1349, 1355 (Fed. Cir. 2010)], he [or she] cannot dismiss so much
      contrary evidence that it appears that he ‘simply failed to consider
      genuinely the evidentiary record before him [or her].’“

                                            16
Paluck ex rel. Paluck v. Sec’y of Health & Hum. Servs., 104 Fed. Cl. at 467 (quoting
Campbell v. Sec’y of Health & Hum. Servs., 97 Fed. Cl. 650, 668 (2011))) (alteration
added). A Special Master is required to acknowledge that “the purpose of the Vaccine
Act’s preponderance standard is to allow the finding of causation in a field bereft of
complete and direct proof of how vaccines affect the human body,” even if the possible
link between the vaccine and the injury is “hitherto unproven.” Althen v. Sec’y of Health
& Hum. Servs., 418 F.3d at 1280; see also Porter v. Sec’y of Health & Hum. Servs., 663
F.3d at 1261. In that vein, “close calls regarding causation are resolved in favor of
injured claimants.” Althen v. Sec’y of Health & Hum. Servs., 418 F.3d at 1280 (citing
Knudsen v. Sec’y of Health & Hum. Servs., 35 F.3d 543, 548–49 (Fed. Cir. 1994)).

       Under the off-Table theory of recovery, a petitioner is entitled to compensation if
he or she can demonstrate, by a preponderance of the evidence, that the recipient of
the vaccine sustained, or had significantly aggravated, an illness, disability, injury, or
condition not set forth in the Vaccine Injury Table, but which was caused by a vaccine
that is listed on the Vaccine Injury Table. See 42 U.S.C. §§ 300aa-11(c)(1)(C)(ii)(I),
300aa-13(a)(1)(A); see also LaLonde v. Sec’y of Health & Hum. Servs., 746 F.3d 1334,
1339 (Fed. Cir. 2014); W.C. v. Sec’y of Health & Hum. Servs., 704 F.3d at 1356
(“Nonetheless, the petitioner must do more than demonstrate a ‘plausible’ or ‘possible’
causal link between the vaccination and the injury; he must prove his case by a
preponderance of the evidence.” (quoting Moberly ex rel. Moberly v. Sec’y of Health &
Hum. Servs., 592 F.3d at 1322)); Hines v. Sec’y of Health & Hum. Servs., 940 F.2d at
1525. While scientific certainty is not required, the Special Master “is entitled to require
some indicia of reliability to support the assertion of the expert witness.” Moberly ex rel.
Moberly v. Sec’y of Health & Hum. Servs., 592 F.3d at 1324; see also Hazlehurst v.
Sec’y of Health & Hum. Servs., 88 Fed. Cl. 473, 479 (2009), aff’d, 604 F.3d 1343 (Fed.
Cir. 2010) (quoting Andreu ex rel. Andreu v. Sec’y of Health & Hum. Servs., 569 F.3d at
1379).

       To establish causation in fact for a Non-Table claim, such as petitioner’s claim in
the above captioned case, a petitioner must satisfy all three of the elements established
by the United States Court of Appeals for the Federal Circuit in Althen v. Secretary of
Health & Human Services, 418 F.3d at 1278. See Sanchez v. Sec’y of Health & Hum.
Servs., 34 F.4th 1350 (Fed. Cir. 2022); Deribeaux ex rel. Deribeaux v. Sec’y of Health &
Hum. Servs., 717 F.3d at 1367; Porter v. Sec’y of Health & Hum. Servs., 663 F.3d at
1249; Moberly ex rel. Moberly v. Sec’y of Health & Hum. Servs., 592 F.3d at 1322;
Pafford v. Sec’y of Health & Hum. Servs., 451 F.3d at 1355; Capizzano v. Sec’y of
Health & Hum. Servs., 440 F.3d 1317, 1324 (Fed. Cir. 2006); C.K. v. Sec’y of Health &
Hum. Servs., 113 Fed. Cl. 757, 766 (2013).

       With regard to the first Althen prong, “a medical theory causally connecting the
vaccination and the injury,” the Federal Circuit in Althen analyzed the preponderance of
evidence requirement as allowing medical opinion as proof, even without scientific
studies in medical literature that provide “objective confirmation” of medical plausibility.
See Althen v. Sec’y of Health & Hum. Servs., 418 F.3d at 1278, 1279–80; see also

                                            17
Shapiro v. Sec’y of Health & Hum. Servs., 105 Fed. Cl. 353, 358 (2012), aff’d, 503 F.
App’x 952 (Fed. Cir. 2013). In rejecting a requirement that a claimant under the Vaccine
Act prove confirmation of medical plausibility from the medical community and medical
literature, the Federal Circuit in Althen v. Secretary of Health & Human Services, relied
on Knudsen v. Secretary of Health & Human Services, 35 F.3d 543, 548–49 (Fed. Cir.
1994), in which the Federal Circuit wrote, “to require identification and proof of specific
biological mechanisms would be inconsistent with the purpose and nature of the
vaccine compensation program. The Vaccine Act does not contemplate full blown tort
litigation in the Court of Federal Claims.” Althen v. Sec’y of Health & Hum. Servs., 418
F.3d at 1280. Rather, a petitioner must preponderantly establish that the vaccine at
issue can cause the petitioner’s injury by providing a “‘reputable medical or scientific
explanation’ for its theory.” Boatmon v. Sec’y of Health & Hum. Servs., 941 F.3d 1351,
1359 (Fed. Cir. 2019) (quoting Moberly ex rel. Moberly v. Sec’y of Health and Hum.
Servs., 592 F.3d at 1322). “While it does not require medical or scientific certainty, it
must still be ‘sound and reliable.’” Id. (quoting Knudsen v. Sec’y of Health & Hum.
Servs., 35 F.3d at 548–49).

        The second prong of the Althen test requires the petitioner to demonstrate “a
logical sequence of cause and effect showing that the vaccination was the reason for
the injury” by a preponderance of the evidence. Althen v. Sec’y of Health & Hum.
Servs., 418 F.3d at 1278; see also Sanchez v. Sec’y of Health & Hum. Servs., 34 F.4th
at 1353; Pafford v. Sec’y of Health & Hum. Servs., 451 F.3d at 1355. In order to prevail,
the petitioner must show “that the vaccine was not only a but-for cause of the injury but
also a substantial factor in bringing about the injury.” Althen v. Sec’y of Health & Hum.
Servs., 418 F.3d at 1278 (quoting Shyface v. Sec’y of Health & Hum. Servs., 165 F.3d
1344, 1352–53 (Fed. Cir. 1999)). In Capizzano v. Secretary of Health and Human
Services, 440 F.3d at 1326, the Federal Circuit stated, “‘[a] logical sequence of cause
and effect’ means what it sounds like-the claimant’s theory of cause and effect must be
logical. Congress required that, to recover under the Vaccine Act, a claimant must prove
by a preponderance of the evidence that the vaccine caused his or her injury.”
Capizzano v. Sec’y of Health & Hum. Servs., 440 F.3d at 1326 (quoting 42 U.S.C.
§§ 300aa–11(c)(1)–13(a)(1) (2006)); see also Cozart v. Sec’y of Health & Hum. Servs.,
126 Fed. Cl. 488, 498 (2016) (quoting Althen v. Sec’y of Health & Hum. Servs., 418
F.3d at 1278).9

9 The third prong of the Althen test requires the petitioner to demonstrate, by a
preponderance of evidence, that there is “a proximate temporal relationship between
vaccination and injury.” Althen v. Sec’y of Health & Hum. Servs., 418 F.3d at 1278; see
also Sanchez v. Sec’y of Health & Hum. Servs., 34 F.4th at 1353. The United States
Court of Appeals for the Federal Circuit emphasized the importance of a temporal
relationship in Pafford v. Secretary of Health and Human Services, when it noted that,
“without some evidence of temporal linkage, the vaccination might receive blame for
events that occur weeks, months, or years outside of the time in which scientific or
epidemiological evidence would expect an onset of harm.” Pafford v. Sec’y of Health &
Hum. Servs., 451 F.3d at 1358. “Evidence demonstrating petitioner’s injury occurred
within a medically acceptable time frame bolsters a link between the injury alleged and
                                            18
        According to the Federal Circuit in Capizzano v. Secretary of Health and Human
Services, evidence used to satisfy one of the Althen prongs may overlap with and be
used to satisfy another prong. See Capizzano v. Sec’y of Health & Hum. Servs., 440
F.3d at 1326 (“We see no reason why evidence used to satisfy one of the Althen III
[Althen v. Sec’y of Health & Hum. Servs., 418 F.3d at 1274] prongs cannot overlap to
satisfy another prong.” (alteration added)). If a petitioner satisfies the Althen burden and
meets all three prongs of the test, the petitioner prevails, “unless the government
demonstrates that the injury was caused by factors unrelated to the vaccine.” Sanchez
v. Sec’y of Health & Hum. Servs., 34 F.4th at 1353 (alteration added) (citing 42 U.S.C.
§ 300aa-13(a)(1)(B)); see also Knudsen v. Sec’y of Health & Hum. Servs., 35 F.3d at
547 (brackets in original; quotation omitted).

       As indicated above, in the case currently before the court, petitioner argues that
denial by the Chief Special Master of his “repeated requests to retain an infectious
disease expert resulted in an unbalanced review of Petitioner’s presentation of Althen
Prong 2 and constituted an abuse of discretion under the Circumstances of this Case.”
(capitalization in original). Petitioner also asserts that although
       [r]espondent argued in his responding brief that an influenza-like illness,
       an upper respiratory infection, or cytomegalovirus likely caused
       Petitioner’s GBS. There exists no evidence in this case that a pathogen
       was present in [K.A.] prior to the onset of his GBS that supports
       Respondent’s speculation about an infectious causal factor for [K.A.]’s
       GBS.”
(alterations added). Petitioner continues:
       Chief Special Master Corcoran relied upon the existence of an intercurrent
       upper respiratory infection as the likely cause of onset of GBS in rejecting
       Petitioner’s showing of Althen prong 2. Thus, in the court’s own view,
       Petitioner could not have established his claim by a preponderance of the
       evidence without a more effective counterpoint to an unidentified
       infectious disease as causative agent.
        Petitioner also asserts that “Chief Special Master Corcoran’s slant in assessing
the evidence was manifest in his pronouncement, not founded in the record, that [K.A.]’s
initial symptoms, ‘appear[ed] broader than the common post-vaccination malaise.’”

the vaccination at issue under the ‘but-for’ prong of the causation analysis.” Id. (citing
Capizzano v. Sec’y of Health & Hum. Servs., 440 F.3d at 1326). The court notes that
Chief Special Master’s conclusions regarding the third prong of the Althen test was not
one of the bases for petitioner’s numbered objections in petitioner’s May 18, 2022
Motion for Review of the Chief Special Master’s Entitlement Decision, and, therefore, is
not addressed in this Opinion. The court also notes that in the Chief Special Master’s
Entitlement Decision, the Chief Special Master indicated, “because the claim fails on the
first two Althen prongs, Petitioner’s ability to preponderantly support the third prong
does not avail him.”
                                             19
(second alteration in original). Petitioner asserts that the “only undisputed diagnosis was
the post-vaccination onset of GBS.” Petitioner argues that
       [c]learly, the proposition that the initial symptoms, “appear[ed] broader”
       than would be induced by vaccination should have been addressed by an
       infectious disease expert retained by the Petitioner, who would be familiar
       with both symptoms of vaccination and infection. Multiple critical aspects
       of this case required clarification by – and even turned upon – the
       expertise and perspective of an infectious disease specialist presented by
       the Petitioner.
Only after more than three years and seven months after petitioner filed his petition for
compensation and after petitioner filed the first four expert reports authored by Dr.
Steinman did petitioner belatedly urge that an infectious disease expert could have
“opined on the relationship” between petitioner’s initial flu-like symptoms and those
present at the onset of his GBS, despite the presence of URI symptoms, which, as the
Chief Special Master noted, the majority of [petitioner’s] treaters deemed the URI most
likely causal.” (alteration added).
      Moreover, as noted above, Dr. Collins filed expert reports on December 4, 2017,
June 13, 2018, and May 7, 2019, all of which addressed, and rejected, petitioner’s initial
causation theory that aluminum adjuvant in the Tdap vaccine caused petitioner’s GBS.
Further, even after Dr. Collins, in her fourth and final expert report dated January 23,
2020, addressed petitioner’s alternate theory of molecular mimicry on behalf of the
respondent, petitioner had an opportunity to file another expert report by Dr. Steinman
on June 22, 2020.

        With respect to the Chief Special Master’s review by the expert reports authored
Dr. Steinman offered by petitioner, petitioner argues that Chief Special Master Corcoran
“characterized Dr. Steinman’s challenge to Respondent’s reliance upon an unidentified
‘influenza-like illness’ as mere ‘quibbling.’” Petitioner argues that the Chief Special
Master’s “persistent criticism and denigration of Petitioner’s lone expert implicates the
harm that flowed from the Court’s refusal, over the course of assignment to two special
masters, to permit retention of the relevant experts.” In the Motion for Review in this
court, petitioner argues, “[w]hile Dr. Steinman has unparalleled qualifications in
neurology and neuroimmunology and specific areas such as molecular mimicry, his
singular focus upon the non-specificity of terms such as ‘influenza-like illness’ during his
dialogue with Dr. Collins may reflect the limits of his expertise in the separate field of
infectious disease.” (citation omitted). Petitioner also stresses that the Chief Special
Master criticized petitioner’s expert for his lack of expertise in infectious diseases while
denying petitioner the opportunity to retain an expert qualified in the field. Petitioner
further states that “the presiding special masters[10] failed to afford each party a full and

10 The court notes that petitioner’s request “to file an expert report from an infectious
disease specialist and an expert report from a specialist in biostatistics” was denied on
June 12, 2020, by Special Master Roth before the case was transferred to the Chief
Special Master. Chief Special Master Corcoran, however, also did not grant petitioner’s
                                             20
fair opportunity to present his case, failed to afford a hearing, and failed to create a
record sufficient to allow review of the respective orders denying the retention of
experts.” (alteration added).

        In response, respondent argues that the Chief Special Master, pursuant to
Vaccine Rule 8(a), gave “each party a full and fair opportunity” to present their case,
and also notes that a Special Master “will determine the format for taking evidence and
hearing argument based on the specific circumstances of each case and after
consultation with the parties.’” Respondent notes that, in the above captioned case,
petitioner “filed five expert reports over three years, modified his causation theory, and
now seeks, after an unexplained multi-year delay, additional experts to cover the same
ground already covered by Dr. Steinman.” (alteration added). Respondent also points
out that petitioner’s “medical record, filed between August 2016 and January 2017, is
replete with references to petitioner’s ILI/URI as a potential cause of his GBS.”
Respondent argues that in its February 23, 2017 Rule 4(c) report, respondent
“specifically identified petitioner’s ILI/URI as evidence against entitlement.” Therefore,
according to respondent, “petitioner, represented by experienced counsel, could have
retained an infectious disease expert then. Instead, he chose to proceed with Dr.
Steinman alone to address the ILI/URI issue until objecting at the ‘eleventh-hour.’” In
addition, according to respondent,
       in his five reports, Dr. Steinman variously discussed epidemiological
       studies, the “possibility of an infectious disease etiology,” and opined that
       “the priority of the potential CMV or EBV infections in triggering disease is
       lower than the likelihood that the vaccination triggered the disease.” Thus,
       not only did petitioner have both the time and opportunity before the case
       was adjudicated to retain an infectious disease expert, petitioner’s expert
       actually did address the ILI/URI issue in regard to his GBS.
(internal citations omitted).
        Further, respondent argues that the “Chief Special Master appropriately
considered petitioner’s own detailed reports of flu-like symptoms and the comments of
his treating physicians regarding ILI/URI” because a Special Master “‘is entitled to
consider the record as a whole in determining causation, especially in a case involving
multiple potential causes acting in concert, and no evidence should be embargoed from
the special master’s consideration[.]’” (quoting Stone v. Sec’y of Health & Hum. Servs.,
676 F.3d 1373, 1380 (Fed. Cir. 2012)). Finally, respondent argues that “[t]he Chief
Special Master correctly considered the ILI/URI evidence in evaluating the sufficiency of
petitioner’s proof that the Tdap vaccine did cause his GBS under Althen prong 2.”

       In reaching a conclusion in each vaccine case, the Special Master considers the
factual and supporting record in a petitioner’s case as filed before the Special Master
including the petitioner’s contemporaneous medical records, as well as expert reports, if
any. The expert reports are reviewed by the Special Master for their content and for the

renewed request for expert reports from an infectious disease specialist and a specialist
in biostatistics.
                                            21
expert’s expertise and credibility. See Broekelschen v. Sec’y of Health & Hum. Servs.,
618 F.3d at 1348 (quoting Hines v. Sec’y of Health & Hum. Servs., 940 F.2d at 1528);
see also Munn v. Sec’y of Health & Hum. Servs., 970 F.2d at 870. When addressing
credibility, previously published expert reports and testimony by the same expert, may
be reviewed and considered by the Special Master. Repeat experts who have testified
or submitted expert reports regularly in a particular field have to live with, or explain
away, their previous testimony and their previously filed expert reports.

        In weighing the expertise and credibility of both petitioner’s and respondent’s
experts, the Chief Special Master, in his Entitlement Decision, did “not give substantial,
if any, weight to Dr. Steinman’s objections that the term of art ‘influenza-like illness’ to
describe Petitioner’s URI is scientifically indeterminate—since filed record evidence
from competent medical and scientific professionals employ the term in their own
studies.” In his Entitlement Decision, Chief Special Master Corcoran addressed Dr.
Steinman’s role as an expert for petitioner during the pendency of the case, as well as
times he had previously testified in vaccine cases. For example, the Chief Special
Master criticized Dr. Steinman’s fifth and final report as “reflect[ing] the same bickering
quality, or wholesale reproduction of prior arguments, that characterizes most of his
prior reports filed in this case.” Additionally, the Chief Special Master wrote in a footnote
in his Entitlement Decision, that “Dr. Steinman also engaged in conduct I have in the
past criticized him for: commenting on the standards governing Program cases, and
elaborating on how he performs his role as expert, rather than simply providing the
medical/scientific opinion for which he has been retained.” In the above captioned case,
Chief Special Master Corcoran also criticized what he called “Dr. Steinman’s legal
pronouncements” and correctly noted that expert witnesses are not allowed to interpret
“the meaning of Program caselaw or the applicable legal standards.” In this regard, the
Chief Special Master wrote that “[n]one of Dr. Steinman’s reports in this case were
prepared while I was presiding over this matter—but in future cases in which Dr.
Steinman is retained that are assigned to me, I will not compensate time spent on
opinions on legal issues that he is not qualified to address.” (emphasis in original). The
Chief Special Master summarized his view of Dr. Steinman’s role in the above
captioned case by noting: “Altogether, Dr. Steinman offered more than 70 pages of
expert opinion on this matter, (as discussed below and throughout this Decision), I do
not conclude the significant effort was ultimately well spent.”

        The Chief Special Master, however, gave more credit to respondent’s expert Dr.
Collins. Chief Special Master Corcoran noted that in Dr. Collins’ fourth and final expert
report, “Dr. Collins also emphasized again her opinion that an influenza-like illness was
a far more likely cause of Petitioner’s GBS in this case,” and determined that “Dr.
Collins also persuasively showed that many facially-reliable studies had included
‘influenza-like illness’ as a potentially causal agent of GBS, despite Dr. Steinman’s
protestations.”

      All Special Masters have a responsibility to “afford[ ] each party a full and fair
opportunity to present its case and create[e] a record sufficient to allow review of the
special master’s decision.” See Kreizenbeck v. Sec’y of Health & Hum. Servs., 945 F.3d

                                             22
1362, 1366 (Fed. Cir. 2020); see also Doles v. Sec’y of Health & Hum. Servs., 159 Fed.
Cl. 241, 246 (2022) (“[T]he special masters are bound by an obligation to be fair to both
parties, and to provide both parties the opportunity to present a case”) (emphasis in
original). A Special Master, however, also has the responsibility and authority to
“determine the format for taking evidence and hearing argument based on the specific
circumstances of each case.” Vaccine Rule 3(b)(2), 8(a) (2021). Although Chief Special
Master Corcoran’s choices of words regarding Dr. Steinman and his expert reports may
have been pointed and critical, his comments as a veteran Special Master were based
on Chief Special Master Corcoran’s varied experiences in the Vaccine Program,
including with Dr. Steinman as an expert witness. As explained by another Judge of the
United States Court of Federal Claims:

       That the Special Master “was far more impressed and persuaded by the
       testimony of Dr. Wiznitzer” does not show any bias, and shows that the
       Special Master in fact did exactly what the Federal Circuit has
       admonished special masters to do in vaccine cases. See Porter, 663 F.3d
       at 1250 (“Indeed, 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
       decision shows that the Special Master considered the testimony of both
       experts, and indeed, it recaps a significant amount of information from
       both experts, but in the end, the Master concluded that Dr. Wiznitzer was
       the more trustworthy. The Special Master, as fact finder, “has broad
       discretion in determining credibility because he saw the witnesses and
       heard the testimony.” Bradley, 991 F.2d at 1575. For this reason, the
       Special Master’s determination on credibility is “virtually unreviewable,”
       Porter, 663 F.3d at 1251, and to the extent that it is reviewable, this Court
       sees nothing arbitrary or capricious in the Special Master’s findings here.

Vaughan v. United States, 107 Fed. Cl. 212, 224 (2012).

        After weighing all of the parties’ submissions, including the numerous expert
reports and petitioner’s medical records, Chief Special Master Corcoran found Dr.
Steinman’s opinions less credible than those of Dr. Collins. The weight to be given to
each expert is within the discretion of each trier of fact, based on the facts in the record
in each case. See Porter v. Sec’y of Health & Hum. Servs., 663 F.3d at 1249. This court
notes that initially Dr. Steinman offered a causation theory that the Tdap vaccine’s
aluminum adjuvant can cause GBS. Only in his fourth expert report did Dr. Steinman
proffer molecular mimicry as a new causation theory, which he contended co-existed
with his prior aluminum adjuvant theory. Petitioner tries to justify his delay for requesting
to add an infectious disease expert late in the case, stating that “[w]hile Respondent
argues that the issue of influenza-like-illness was already apparent, both the extent of
that reliance and the ambiguity and limited value of that approach was not apparent until
Respondent’s expert, Dr. Collins, had made her case across her expert reports.”
Because petitioner’s contemporaneous medical records from the time shortly after his
Tdap vaccination, when he was medically examined, to the time the record was closed

                                             23
prior to the Chief Special Master’s review, and the issuance of his decision, there are
repeated references to the existence of an influenza-like illness or upper respiratory
illness, as a potential cause of petitioner’s GBS. Petitioner, therefore, was on notice of
the URI/ILI as a potential cause of his GBS well before he filed his petition with the
Office of Special Masters. Moreover, respondent’s Rule 4(c) report, filed on February
23, 2017, specifically identified petitioner’s ILI/URI as evidence against entitlement, for
petitioner to consider.
        This court notes that petitioner’s contemporaneous medical records, which
receive great evidentiary weight, contained repeated references to his URI/ILI as a
possible causation of his medical issues and a factor in his Guillain-Barré syndrome
following his Tdap vaccination. See Cucuras v. Sec’y of Health & Hum. Servs., 993 F.2d
1525, 1528 (Fed. Cir. 1993) (“Medical records, in general, warrant consideration as
trustworthy evidence. The records contain information supplied to or by health
professionals to facilitate diagnosis and treatment of medical conditions. With proper
treatment hanging in the balance, accuracy has an extra premium. These records are
also generally contemporaneous to the medical events.”). In petitioner’s case, a number
of petitioner’s contemporaneous medical records indicate, not only the existence of a
URI/ILI, but that the URI/ILI was likely the cause of petitioner’s GBS. Chief Special
Master Corcoran specifically relied on these medical records when evaluating the
likelihood that the Tdap vaccine caused petitioner’s GBS. Chief Special Master
Corcoran indicated that “not only is there incontrovertible evidence that Petitioner first
experienced URI symptoms before neurologic-related symptoms, but also that the
majority of his treaters deemed the URI most likely causal. The vaccine does not
deserve greater weight simply because it is ‘known’ whereas the precise nature of the
infection is not.” (emphasis in original). The court notes that Chief Special Master
Corcoran stated in his Entitlement Decision that in Dr. Collins’ fourth and final expert
report, “Dr. Collins also emphasized again her opinion that an influenza-like illness was
a far more likely cause of Petitioner’s GBS in this case.”
        Based on the contemporaneous medical records in the record before the Chief
Special Master, the relative weight and credibility of the theories advanced by the expert
witnesses for each party to the litigation, the decision issued by Chief Special Master
Corcoran was reasonable and was supported by Dr. Collins’ theory that petitioner’s
URI/ILI more than likely caused the GBS. Therefore, this court determines that Chief
Special Master’s decision not to grant to petitioner’s request for additional experts, after
petitioner filed numerous contemporaneous medical records, and five expert reports
author by Dr. Steinman, did not result in denying petitioner a full and fair opportunity to
present his case.
        Although not one of his specific numbered objections, petitioner also asserts that
the Chief Special Master’s decision to deny a hearing in his case was unreasonable.
Petitioner argues that the Chief Special Master’s denial of a hearing constituted a failure
“to afford each party a full and fair opportunity to present his case.” Petitioner argues
that a hearing was necessary because “Chief Special Master Corcoran has called into
question the credibility of Dr. Steinman as a witness,” and “a hearing would afford Dr.
Steinman, a true expert in this area, the opportunity to clarify his position as to why the
theory of molecular mimicry, in this case, addresses the issues of inflammation and

                                            24
pathology and their relationship to Guillain Barre Syndrome (GBS).” The court notes
that petitioner’s first request for a hearing appears to have been made on October 12,
2021, after Dr. Steinman had submitted all five of his expert reports in the above
captioned case. Petitioner argues that the denial of a hearing “prejudiced Petitioner in
the proceedings” because it “limited the court’s ability to assess the evidence proffered
by Dr. Steinman, the Petitioner’s sole expert witness.” In response, respondent argues,
citing Vaccine Rule 8(d) (2021), that “[i]t is well-established, however, that a special
master ‘may decide a case on the basis of written submissions without conducting an
evidentiary hearing.’” Respondent also cites 42 U.S.C. § 300-aa-12(d)(3)(B)(v), stating
that Special Masters have it within their discretion to allow “such hearings as may be
reasonable and necessary.” Respondent indicates that Chief Special Master Corcoran
found that “a hearing was not needed to decide this case.” Respondent argues:
       Since the filing of the Rule 4(c) report, petitioner has known respondent’s
       position on petitioner’s ILI/URI as a relevant factor regarding vaccine
       causation for his GBS. Petitioner cannot now reasonably object after
       initially agreeing to a ruling on the record by belatedly at the “eleventh-
       hour” requesting a hearing in his reply brief. C.f. Novosteel SA v. U.S.,
       Bethlehem Steel Corp., 284 F.3d 1261, 1274 (Fed. Cir. 2002) (“Raising
       the issue for the first time in a reply brief does not suffice; reply briefs reply
       to arguments made in the response brief—they do not provide the moving
       party with a new opportunity to present yet another issue for the court’s
       consideration.”); see also In re Osterman, 296 F. App’x 900, 902 n.1 (11th
       Cir. 2008) (“[A] passing reference to an issue in a reply brief, offered
       without substantive argument in support, is insufficient to constitute raising
       the issue”). Because the Chief Special Master properly applied the law
       and acted within his discretion in deciding this case on the record, his
       Decision should be affirmed.
(alteration in original).
       As noted above, petitioner’s petition for compensation, dated August 11, 2016,
and petitioner’s initial brief, dated July 2, 2021, did not request for an evidentiary
hearing. When he issued his Entitlement Decision, the Chief Special Master explained
his decision “not to hold a hearing,” which Chief Special Master Corcoran indicated he
understood at the time was “a determination that the parties largely accepted.” In a
footnote, Chief Special Master Corcoran indicated:
       Petitioner’s initial ruling on the record brief did not oppose deciding this
       case on the papers. On Reply, however, Petitioner included a footnote
       setting forth some process objections: that he was denied the opportunity
       to offer his own infectious disease expert (by the special master previously
       assigned to the case) to counter Dr. Collins’s arguments, and that,
       although he noted my discretion to choose how best to decide the case, a
       hearing was warranted since the petitioner’s theories were “closely

                                              25
       contested.”[11] Putting aside the underwhelming and somewhat eleventh-
       hour nature of this objection, I nevertheless determine (as explained
       herein) that the claim could be, and was, fairly adjudicated solely on the
       basis of the papers—and as already noted hearings are not held simply
       because the parties disagree on entitlement.
(internal reference omitted; alteration added). The Chief Special Master also indicated
that “[d]etermining how best to resolve a case is a matter that lies generally within my
discretion,” and that “[i]t was wholly fair to both sides to resolve this case on the papers
and after briefing by the parties.” Chief Special Master Corcoran indicated that “[o]ver
the case’s nearly six years, Petitioner was afforded the opportunity to offer five written
expert reports” and “was also permitted to modify his causation theory entirely, after
Respondent voiced objections to its sufficiency.” (emphasis in original). Moreover, the
Chief Special Master concluded that petitioner’s second theory of causation, molecular
mimicry, is “one with which I have substantial familiarity—meaning I did not need to
hear live testimony from Dr. Steinman to understand or react to it.”
        Courts review a Special Master’s determination to deny an evidentiary hearing
for an abuse of discretion. See Kreizenbeck v. Sec’y of Health & Hum. Servs., 945 F.3d
at 1364 (“We review a special master’s decision to hold an evidentiary hearing for an
abuse of discretion.”); see also Munn v. Sec’y of Health & Hum. Servs., 970 F.2d 863 at
870 n.10. “Determinations subject to review for abuse of discretion must be sustained
unless ‘manifestly erroneous.’” Heddens v. Sec’y of Health & Hum. Servs., 143 Fed. Cl.
at 193 (quoting Piscopo v. Sec’y of Health & Hum. Servs., 66 Fed. Cl. at 53 (citations
omitted)). Moreover, Special Masters have “wide discretion in determining whether to
conduct an evidentiary hearing.” Kreizenbeck v. Sec’y of Health & Hum. Servs., 945
F.3d at 1365; see also Oliver v. Sec’y of Health & Hum. Servs., 900 F.3d 1357, 1364
n.6 (Fed. Cir. 2018) (holding that “Chief Special Master acted within her discretion in
denying” the petitioner’s request for a hearing); Burns v. Sec’y of Health & Hum. Servs.,
3 F.3d at 417 (holding that “the special master acted within her discretion to determine
that an additional [evidentiary] hearing on expert medical testimony was not necessary”)
(alteration added); Simanski v. Sec’y of Health & Hum. Servs., 671 F.3d 1368, 1371
(Fed. Cir. 2012) (noting that “the Vaccine Rules provide that the special masters can
decide cases on written submissions, including, in appropriate cases, by summary
judgment”). Nevertheless, the “special master’s discretion to rule on the record is not
without limitation.” Kreizenbeck v. Sec’y of Health & Hum. Servs., 945 F.3d at 1365.
Because Special Masters are required to “afford[ ] each party a full and fair opportunity
to present its case and creat[e] a record sufficient to allow review of the special master’s
decision,” a special master “must determine that the record is comprehensive and fully
developed before ruling on the record.” Id. at 1366 (alterations in original) (citing

11  A note in petitioner’s October 12, 2021 reply brief stated that “petitioner
acknowledges the Court’s authority to decide this case without an evidentiary hearing
during which the experts’ presentations can be explored.” Petitioner, however, also
stated, “in the context of the present case, where petitioner’s theory is closely
contested, a hearing would supply valuable elaboration of petitioner’s case and a
hearing should be conducted.”
                                            26
Simanski v. Sec’y of Health & Hum. Servs., 671 F.3d at 1380 (finding that it was a
violation of due process for a special master to rule on the record at “an early
procedural stage” before respondent had “present[ed] its position with respect to the
petition and the supporting evidence”) (alteration added)); see also Oliver v. Sec’y of
Health & Hum. Servs., 900 F.3d 1357, 1364 n.6 (Fed. Cir. 2018) (holding that because
“the record was fully developed” and no legal or factual errors necessitated a hearing, it
was within the Chief Special Master’s discretion to deny the petitioner’s request for an
evidentiary hearing); Burns v. Sec’y of Health & Hum. Servs., 3 F.3d at 417.
        Before Chief Special Master Corcoran, the record included petitioner’s medical
history prior to August 12, 2013 when petitioner received the vaccination at issue, his
contemporaneous medical records from 2013 to 2016, as well as five expert reports that
together spanned over seventy pages from petitioner’s expert, Dr. Steinman, as well as
four expert reports from Dr. Collins on behalf of respondent. The record also contained
medical literature included with each of the experts’ reports, including the results of Dr.
Steinman’s BLAST searches. Unlike in Simanski v. Secretary of Health & Human
Services, 671 F.3d at 1380, in which the Federal Circuit found that it was a violation of
due process for a special master to rule on the record at “an early procedural stage,” the
above captioned case was not at an “early procedural stage” based on the length of
time from the filing of the case to when the parties submitted their respective briefs,
which included the time to gather the relevant medical records of petitioner, to produce
the numerous expert reports submitted by both experts, and for time for each expert to
respond to the opposing expert. Moreover, petitioner had two years to file a request for
additional expert(s) to challenge Dr. Collins’ arguments that a URI/ILI caused
petitioner’s GBS. See Hines v. Sec’y of Health & Hum. Servs., 940 F.2d at 1526
(holding that “principles of fundamental fairness to both parties” were not violated when
the petitioner had the opportunity to “discredit” and “rebut” the information (emphasis in
original)).

        Moreover, throughout the pendency of his case, petitioner received multiple
extensions of time to file the expert reports authored by Dr. Steinman. In addition, on
July 29, 2019, almost three years after the petition was filed, Special Master Roth held a
status conference with the parties, during which the respondent indicated that
petitioner’s aluminum adjuvant causation theory was implausible. This prompted Special
Master Roth to allow Dr. Steinman to submitted another expert report regarding
petitioner’s alterative causation theory regarding molecular mimicry as the causation
mechanism, although denying petitioner’s request to submit expert reports at such a
late stage in the case from brand new experts.
      Because a reviewing court should only overturn a special master’s decision if it is
“manifestly erroneous,” see Heddens v. Sec’y of Health & Hum. Servs., 143 Fed. Cl. at
193, and given the contemporaneous medical records in the record before Chief Special
Master Corcoran when he issued his Entitlement Decision, as well as the numerous
extensions and opportunities that petitioner was granted to supplement the record, and
even to propose a second causation theory, it was not manifestly erroneous or an
abuse of discretion for Chief Special Master Corcoran to deny petitioner’s request to

                                            27
submit additional expert testimony or to conclude that petitioner’s case could be decided
on the papers without an evidentiary hearing.
       As to the Chief Special Master’s rejection of petitioner’s molecular mimicry
alternative causation theory, the Chief Special Master reviewed Dr. Steinman’s expert
report on the subject in this case. Before this court, however, petitioner argues that
       the Chief Special Master failed to recognize that the posited medical
       theory of molecular mimicry went well beyond the mere identification of
       homologies between components of the Tdap vaccine and self-antigen
       such as human myelin protein, leading to GBS. The court’s
       misconstruction of the record and incorrect application of the law requires
       vacatur of the Decision. The court compounded its error by holding that
       Petitioner’s causal medical theory was “undercut” by epidemiological
       evidence as to causation for which an expert was denied to Petitioner
       despite requests throughout the case.
Petitioner argues that the “Chief Special Master held, inter alia, that Petitioner could not
rely upon mere amino acid homologies identified through a BLAST search.” (emphasis
in original). Petitioner argues that Dr. Steinman’s expert report went well beyond that
standard and demonstrated how the homologies would produce an immune response.
At the oral argument before this court, petitioner argued that when advancing a theory
of molecular mimicry in vaccine cases, the standard is that it is insufficient to perform
only a BLAST search to demonstrate potential homologies. Additionally, petitioner
argues that Chief Special Master Corcoran’s rejection of the petitioner’s theory of
molecular mimicry and the Chief Special Master’s “undue reliance upon epidemiology in
this context” constitutes an abuse of discretion. Petitioner asserts that the “Chief Special
Master’s Decision turned, in part, upon Baxter I [R. Baxter et al., Acute Demyelinating
Events Following Vaccines: A Case-Centered Analysis, 63 Clin. Infect. Diseases: An
Official Publication of the Infectious Disease Soc. of Am., 1456 (2016) & II [R. Baxter et
al., Lack of Association of Guillain-Barre Syndrome with Vaccinations, 57 Clin. Infect.
Diseases: an Official Publication of the Infectious Diseases Soc. of Am. 197, 203
(2013)].” (alterations added). In the Entitlement Decision, the Chief Special Master
found that “Epidemiologic evidence offered by Respondent also undercuts Petitioner’s
showing.” (capitalization in original). In his Entitlement Decision, the Chief Special
Master wrote:
       Baxter II—a large-scale study identifying no association between Tdap
       and GBS—was particularly harmful. It was far more relevant to Petitioner’s
       claim herein than Baxter I (authored by almost all of the same individuals
       as Baxter II), which Dr. Steinman favorably cited but which only showed a
       possible association between Tdap and ADEM [acute disseminated
       encephalomyelitis]—a distinguishable central nervous system-impacting
       demyelinating disease. The very fact that Dr. Steinman chose to cite
       Baxter I is telling—if one epidemiologic study not fully on point is
       nevertheless supportive of his theory, how can a study directly on point
       (since it involved the injury at issue in this case), and written by largely the

                                             28
       same group of scientific professionals, not also bear on the case’s
       outcome?
(emphasis in original; alteration added).
        Citing the legal analysis of one of his own, prior decisions, Yalacki v. Secretary of
Health & Human Services, 14-278V, 2019 WL 1061429 (Fed. Cl. Spec. Mstr., Jan. 31,
2019), review denied, 146 Fed. Cl. 80 (2019), Chief Special Master Corcoran concluded
that petitioner’s molecular mimicry theory “was not preponderantly shown to be likely
causal,” and stated “that molecular mimicry is not a ‘get out of jail free card’ in the
[Vaccine] Program, entitling claimants who hire Dr. Steinman (or someone else
sufficiently conversant with molecular biology and the relevant databases) to
compensation, merely because it has scientific reliability as a general matter.” Chief
Special Master Corcoran determined:
       Without some reason to further find that the relevant vaccine can be
       causal of the specific injury at issue—however that might be
       demonstrated—establishing a potentiality for molecular mimicry alone
       does not meet the preponderant standard of proof, no matter what degree
       of amino acid identity (sequential or not) Dr. Steinman can demonstrate
       with a BLAST search.
(emphasis in original).
        Petitioner argues that Yalacki decision “does not appear to have considered the
type of multi-layered, filtered investigation utilized by Dr. Steinman in establishing a
theory of molecular mimicry in this case.” Although petitioner appears to agree that the
injury in Yalacki, like the injury here, involves autonomic dysfunction. Petitioner,
however, attempts to distinguish the Yalacki case on the grounds that the petitioner’s
injury in Yalacki was “induced by a different vaccine” and the “evidence (and science)
[in Yalacki] that the cross-reaction would target the self-antigen was undeveloped.”
Respondent does not specifically address petitioner’s use of Yalacki v. Secretary of
Health & Human Services other than to assert that “[t]he Chief Special Master properly
applied the law.”
         Additionally, respondent argues that Dr. Steinman’s efforts, “as correctly noted by
the Chief Special Master, were wholly misplaced. Here, petitioner acknowledges he
cannot rely on mere homologies to establish causation.” Respondent continues that “Dr.
Steinman never adequately addressed the central ‘criticism of his theory’—namely,
although homologies are common and pathogenic cross-reactions are uncommon,
‘most human beings are not plagued by autoimmune pathology.” Respondent further
asserts that “Dr. Steinman never actually provided any relevant, reliable, persuasive
evidence that identify what genetic or environmental factors ‘are necessary before [ ]
self-reactive immune responses to myelin might trigger GBS,’ ‘either theoretically or in
[p]etitioner’s specific case.’” (alterations in original). Respondent asserts that
       the Chief Special Master aptly observed, petitioner relied exclusively on
       mouse models studying experimental autoimmune encephalomyelitis
       (“EAE”) to support the contention that the homologies found could cause

                                             29
       neuroinflammation in humans. But EAE translates to ADEM in humans, “a
       neuroinflammatory demyelinating disorder that impacts the brain and
       spinal cord.” Petitioner never explained how ADEM sufficiently compares
       to petitioner’s specific “pharyngeal-cervical-brachial variant” of GBS, or
       even to GBS in general.
(capitalization in original; internal citations omitted).
        Respondent, citing Andreu ex rel. Andreu v. Secretary of Health & Human
Services, 569 F.3d at 1379, states that “the Chief Special Master appropriately
considered the epidemiological evidence submitted by both parties.” Respondent
asserts that epidemiological evidence is not necessary to prove causation under the
Vaccine Act, but that “‘the special master can consider it in reaching an informed
judgment as to whether a particular vaccination likely caused a particular injury.’”
Although petitioner alleges that the Chief Special Master erred in considering
epidemiological evidence, both parties filed epidemiological evidence and analyses, and
according to respondent, “epidemiology is considered by special masters in nearly
every contested Vaccine Program case.” Indeed, Dr. Steinman discussed
epidemiological studies, the “possibility of an infectious disease etiology,” but argued
that “the priority of the potential CMV [cytomegalovirus] or EBV [Epstein-Barr virus]
infections in triggering disease is lower than the likelihood that the vaccination triggered
the disease.” (alterations added). Respondent argues, therefore, that “[t]he Chief
Special Master here acted within his discretion,” in considering epidemiological
evidence and deciding that petitioner did not meet his burden of proof on the first Althen
prong.
        In the case currently before the court, petitioner’s expert, Dr. Steinman,
presented epidemiological evidence by citing the Baxter I study, which the Chief Special
Master found should necessarily allow him to look at the Baxter II study as well.
Notably, epidemiologic evidence can be considered in a special master’s Althen prong
one determination, even though it is not required. See Taylor v. Sec’y of Health & Hum.
Servs., 108 Fed. Cl. at 820 (finding that “the Special Master did not err in considering
epidemiological evidence, along with the clinical record, expert testimony and other
medical literature, to reach her informed judgment that Petitioner’s theory of causation
was more unlikely than not”); see also Andreu ex rel. Andreu v. Sec’y of Health & Hum.
Servs., 569 F.3d at 1379 (finding that “where such [epidemiological] 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” (alteration added)). As
noted by a different Special Master in Pierson v. Secretary of Health & Human Services,
a “petitioner must offer more than superficial invocation of molecular mimicry as the
causal mechanism,” and “[i]t also cannot be enough that a medical expert can simply
identify homologous peptides from a generic BLAST search that are not, in any way,
linked to the biological process that is dysfunctional or has suffered injury.’” Pierson v.
Sec’y of Health & Hum. Servs., No. 17-1136V, 2022 WL 322836, at *25 (Fed. Cl. Spec.
Mstr. Jan. 19, 2022) (quoting Brayboy v. Sec’y of Health & Hum. Servs., No. 15-183V,
2021 WL 4453146, at *19 (Fed. Cl. Spec. Mstr. Aug. 30, 2011)).

                                               30
        The court notes that Dr. Steinman’s molecular mimicry theories have had mixed
success before different Special Masters. A number of Special Masters have
determined causation was not met in instances in which Dr. Steinman argued a theory
of molecular mimicry. See, e.g., Mason v. Sec’y of Health & Hum. Servs., No. 17-
1383V, 2022 WL 600415, at *6, *26 (Fed. Cl. Spec. Mstr. Feb. 4, 2022) (Chief Special
Master Corcoran found that Althen prong one was not met when Dr. Steinman argued
that molecular mimicry could trigger chronic inflammatory demyelinating polyneuropathy
even after his “BLAST searches revealed several common sequences, such as
GSASGVSECRF (shared between MBP and the target antigen of the 2014-2015 flu
vaccine), which had five of eleven identical amino acids, and he proposed as a result
that this homology with vaccine components was sufficient for a damaging cross-attack
by immune cells.”); D.G. v. Sec’y of Health & Hum. Servs., No. 11-5777V, 2019 WL
2511769, at *128, *193 (Fed. Cl. Spec. Mstr. May 24, 2019) (Special Master Millman
found no causation in fact when “Dr. Steinman said he talks a lot about molecular
mimicry in this case, but he does not have a known molecular mimic that he can
identify.”); Chinea v. Sec’y of Health & Hum. Servs., No. 15-095V, 2019 WL 1873322, at
*15 (Fed. Cl. Spec. Mstr. Mar. 15, 2019) (Chief Special Master Corcoran found no
causation when “Dr. Steinman next proposed a mechanism by which the flu vaccine
could have caused Mrs. Chinea’s GBS.”); Perez v. Sec’y of Health & Hum. Servs., No.
10–659V, 2015 WL 9483680, at *7, *13 (Fed. Cl. Spec. Mstr. Dec. 8, 2015) (Special
Master Hamilton-Fieldman found petitioner did not meet Althen prong one when Dr.
Steinman argued that molecular mimicry was the reason that petitioner’s tetanus
vaccine caused his GBS.); but see Pierson v. Sec’y of Health & Hum. Servs., 2022 WL
322836, at *12, *39 (Special Master Horner that causation-in-fact was proven
preponderantly in cases in which “Dr. Steinman base[d] his theory of how the Prevnar
13 vaccine can cause GBS through the concept of molecular mimicry.” (alteration
added)); Koller v. Sec’y of Health & Hum. Servs., No. 16-439V, 2021 WL 5027947, at
*8, *23 (Fed. Cl. Spec. Mstr. Oct. 8, 2021) (Special Master Gowan held that all three
Althen prongs were met after Dr. Steinman used molecular mimicry to argue that the
Prevnar 13 vaccine caused petitioner’ GBS.). The court notes, of course, that each of
above cited decisions of the Special Masters was based specifically on the medical
histories and facts of the specific petitioners involved. Moreover, as explained by the
Federal Circuit in Boatmon:
      To the extent the Court of Federal Claims required that special masters
      cite and distinguish the decisions of other special masters, it was
      incorrect. As the Court of Federal Claims itself acknowledged, “[a] Special
      Master is not bound to follow the opinions of other Special Masters.” Id.;
      see also Hanlon v. Sec’y of Health & Human Servs., 40 Fed. Cl. 625, 630
      (1998) (“Special masters are neither bound by their own decisions nor by
      cases from the Court of Federal Claims, except, of course, in the same
      case on remand.”), aff'd, 191 F.3d 1344 (Fed. Cir. 1999). The government
      also acknowledges this on appeal. Appellee’s Br. 18 n.1 (“The decisions of
      other special masters . . . are not binding precedent.”); id. at 22 (“[S]pecial
      masters’ decisions are non-binding.”). By extension, special masters are
      not required to distinguish non-binding decisions of other special masters.
      That is, in part, because “[c]ausation in fact under the Vaccine Act is . . .

                                            31
       based on the circumstances of the particular case.” Knudsen, 35 F.3d at
       548.

Boatmon v. Sec’y of Health & Hum. Servs., 941 F.3d at 1358–59 (alterations in original).

       The court has reviewed petitioner’s objection that the “Chief Special Master failed
to recognize that the posited medical theory of molecular mimicry went well beyond the
mere identification of homologies between components of the Tdap vaccine and self-
antigen such as human myelin protein, leading to GBS.” Petitioner did not offer reliable
evidence to support the petitioner’s theory that molecular mimicry between the Tdap
antigens and self-structures associated with the initial attack on petitioner’s nerves was
the mechanism driving the autoimmune process. Therefore, based on the record before
Chief Special Master Corcoran, this court finds that the Chief Special Master’s decision
that petitioner has not established by a preponderance of the evidence that the Tdap
vaccine likely caused the production of antibodies associated with autonomic damage
or interference sufficient to cause GBS and that those same antibodies did lead to a
pathogenic process was not arbitrary or capricious, or an abuse of discretion.
       Petitioner also argues that Chief Special Master Corcoran applied the wrong
evidentiary standard to the first Althen prong, and argues that the correct legal standard
is whether it is “biologically plausible,” not whether petitioner has preponderantly
established, that the Tdap vaccine could have caused GBS. In response, respondent
argues “[t]he Chief Special Master properly required petitioner to present preponderant
evidence in support of Althen prong 1, and correctly noted that Federal Circuit
precedent requires a petitioner to present more than a ‘plausible theory’ of vaccine
causation.”
       In his Entitlement Decision, Chief Special Master Corcoran noted:
       Before discussing the success of Petitioner’s Althen prong one showing,
       review of his framing of the legal standard applicable is warranted. For
       Petitioner fully misstates that standard, proposing a version that, if
       adopted, would obliterate the existing distinction between Table and non-
       Table claims in the Vaccine Program. Reply at 3. As I noted above, the
       most recent controlling/precedential Federal Circuit caselaw directly
       addressing the subject states explicitly that the first Althen prong requires
       a preponderant showing—just like the other two prongs. Boatmon, 941
       F.3d at 1359; LaLonde, 746 F.3d at 1339; see also Moberly, 592 F.3d at
       1322.
(emphasis in original).
      Consistent with petitioner’s arguments before the Chief Special Master, in his
Motion for Review in this court, petitioner cites to a decision of the Chief Special Master
in Morgan v. Secretary of Health & Human Services, No. 15-1137V, 2019 WL 7498665
(Fed. Cl. Spec. Mstr. Dec. 4, 2019), review denied, 148 Fed. Cl. 454 (2020), aff’d, 850
F. App’x 775 (Fed. Cir. 2021)), a recent decision by a Judge of the United States Court
of Federal Claims reversing Chief Special Master Corcoran’s decision in J. v. Secretary

                                            32
of Health & Human Services, 155 Fed. Cl. 20 (2021), and a recent, non-precedential
Federal Circuit decision in Kottenstette v. Secretary of Health & Human Services, No.
2020-2282, 861 F. App’x 433 (Fed. Cir. 2021), in an attempt to argue that the current
legal standard under the first Althen prong is whether it is biologically plausible
petitioner’s Tdap vaccine could have caused GBS. Despite the petitioner’s attempts to
refashion the first Althen prong standard, in 2019, the Federal Circuit in Boatmon v.
Secretary of Health & Human Services, 941 F.3d 1351, reiterated the Federal Circuit’s
long standing holding that a petitioner bears the burden to prove actual causation by a
preponderance of the evidence.12 The Federal Circuit in Boatmon explained:

      In off-Table cases like this one, it is the petitioners’ burden to prove actual
      causation by a preponderance of the evidence. Moberly, 592 F.3d at
      1322. The Vaccine Act “relaxes proof of causation for injuries satisfying
      the Table[,] . . . but does not relax proof of causation in fact for non-Table
      Injuries.” Id. (quoting Grant, 956 F.2d at 1148). A petitioner must provide a
      “reputable medical or scientific explanation” for its theory. Id. While it does
      not require medical or scientific certainty, it must still be “sound and
      reliable.” Knudsen, 35 F.3d at 548–49.

                                           ...

      We have consistently rejected theories that the vaccine only “likely
      caused” the injury and reiterated that a “plausible” or “possible” causal
      theory does not satisfy the standard. Moberly, 592 F.3d at 1322 (rejecting
      a “more relaxed standard” of whether the condition was “likely caused” by
      the vaccine and reiterating that “proof of a ‘plausible’ or ‘possible’ causal
      link between the vaccine and the injury . . . is not the statutory standard”);
      see also LaLonde, 746 F.3d at 1339 (“However, in the past we have made
      clear that simply identifying a ‘plausible’ theory of causation is insufficient

12The court notes that the Federal Circuit appears to have issued one precedential
decision on the issue of the correct legal standard for causation since the Boatmon
decision. See Kirby v. Sec'y of Health & Hum. Servs., 997 F.3d 1378. In Kirby, the
Federal Circuit observed that

      [t]he government relies on Boatmon v. Secretary of Health & Human
      Services, 941 F.3d 1351, 1359 (Fed. Cir. 2019), but that case is inapt
      because the special master there “articulated a lower ‘reasonable’
      standard” in assessing the petitioners’ medical theory of causation. Here,
      by contrast, the special master recited the correct legal standard. J.A. 33
      (“[P]etitioners must provide a reputable medical theory . . . based on a
      sound and reliable medical or scientific explanation.”) (internal quotation
      marks omitted).

Kirby v. Sec’y of Health & Hum. Servs., 997 F.3d at 1384 (alterations in original).
                                            33
       for a petitioner to meet her burden of proof.” (quoting Moberly, 592 F.3d at
       1322)).

Boatmon v. Sec’y of Health & Hum. Servs., 941 F.3d at 1359–60 (emphasis and
alterations in original). Chief Special Master Corcoran properly cited to the Federal
Circuit’s precedential decision in Boatmon v. Secretary of Health & Human Services, to
conclude that petitioner must present preponderant evidence to prevail under the first
Althen prong. Therefore, this court finds that Chief Special Master Corcoran applied the
correct legal standard for petitioner to meet the first Althen prong, which as determined
above, petitioner failed to meet.

       Petitioner also “seeks review of the Chief Special Master’s conclusion that
Torday v. Secretary of Health & Human Services, No. 07-372V, 2009 WL 5196163
(Fed. Cl. Spec. Mstr. December 10, 2009), is not ‘useful’ to disposition of the case at
bar.” (internal citation omitted). The court notes that the Chief Special Master only
referenced Torday twice in his Entitlement Decision, both times in footnotes. The Chief
Special Master noted in a footnote:
       As Respondent observed in his opposition brief, Dr. Steinman’s misplaced
       reliance on Torday as requiring specification of a precise infection to
       counter the known quantity of a vaccination really invokes a Shyface-like
       analysis from a case where more than one factor was deemed potentially
       causal, leading the special master to give less weight to the unknown
       precise nature of the infection. Torday, 2009 WL 5196163, at *3–4.

Additionally, in a separate footnote, Chief Special Master Corcoran stated:

       Respondent herein also reacted directly to Dr. Steinman’s non-medical
       exegesis into Vaccine Program legal standards, noting that the case he
       cited to defend his view that a known vaccine should be favored as causal
       over a non-specifically identified infection did not quite mean what he
       represented. Opp. at 27–28, citing Torday v. Sec’y of Health & Hum.
       Servs., No. 07-372V, 2009 WL 5196163, at *3–4 (Fed. Cl. Spec. Mstr.
       Dec. 10, 2009). Torday, Respondent maintained, stood only for the
       proposition that when it was undisputed that the vaccine at issue and an
       unspecified illness could be causal, and the evidence was otherwise
       deemed close, it was reasonable to find the vaccine as causal. Here, by
       contrast, Dr. Collins and Respondent did not concede the Tdap vaccine
       was causal. Opp. at 28. Respondent’s reading of Torday is superior to Dr.
       Steinman’s—and it only underscores why medical/scientific experts like
       Dr. Steinman are better off not opining on the meaning of Program
       caselaw or the applicable legal standards (although as discussed in this
       Decision, I give no weight at all to Dr. Steinman’s legal pronouncements,
       and do not otherwise deem Torday a useful guiding decision).

(emphasis in original).

                                           34
      Petitioner claims that “[w]hile Respondent has not conceded that the Tdap
vaccine can be causal to Petitioner’s development of GBS, a court may find that it can
be causal and apply the logic of Torday here.” Petitioner argues:

      All that is known about the days immediately after vaccination is that there
      were symptoms, which form the basis for Respondent's position in this
      case. It is not known to what these symptoms were attributable. There is
      no direct evidence that an infectious disease existed, at all. The symptoms
      may have been attributable to the formative stage of GBS, or perhaps
      another explanation. A court, in weighing a speculative, possibly non-
      existent infectious disease, without identification or specificity, could
      reasonably find recourse to the method employed in Torday, whereby
      preponderance was established, by just a feather's weight, to a known
      causal factor such as vaccination.

       Respondent challenges petitioner’s reading of Torday, and correctly points out
that “Torday is nonprecedential, and the Chief Special Master is not bound by its
analysis. Nevertheless, the Chief Special Master clearly considered Torday
distinguishable from the present case.” (citation omitted).
        In Torday, the petitioner developed GBS after receiving the flu vaccine. See
Torday v. Sec’y of Health & Hum. Servs., 2009 WL 5196163, at *1. Expert witnesses for
petitioner Torday and the respondent disagreed as to whether the vaccine or an
intervening upper respiratory infection caused petitioner Torday’s GBS. See id. at *3. In
Torday, then-Chief Special Master Golkiewicz indicated that “the issue to be decided is
actually quite narrow” because both experts agreed that the vaccine or an upper
respiratory infection could have caused petitioner’s GBS and that both met the third
Althen prong. See id. In Torday, then-Chief Special Master Golkiewicz stated:

      The preponderance of evidence standard is often described as 50 percent
      plus a feather. In this case, the undersigned interprets the experts’
      testimony to be that the vaccine and URI are potentially of equal
      culpability. However, when forced to choose, the experts disagree for the
      reasons stated as to which potential cause gets the feather. In resolving
      this case, the undersigned accepts and credits Dr. Steinman’s logic that
      the known causative agent, the vaccine, should be weighted more heavily
      than the unknown agent causing the URI, which may or may not be a
      potential cause of GBS. Thus, the undersigned finds that the 50 percent
      and the feather goes to the vaccine as the cause of Mr. Torday’s GBS.

Id. at *4 (alteration added). In the Torday decision, then-Chief Special Master
Golkiewicz indicated that he ruled in favor of petitioner Torday “by the slimmest of
margins.” Id.

      As noted above, in his Entitlement Decision for the above captioned case, Chief
Special Master Corcoran indicated he did not “deem Torday a useful guiding decision.”

                                           35
Notably, the vaccine at issue in Torday, an influenza vaccination, was different than the
Tdap vaccine administered to petitioner in the above captioned case.

       As Chief Special Master Corcoran stated in his Entitlement Decision, “it is
incorrect that evidence regarding possible alternative causes should not be included in
a special master’s weighing, absent definitive proof of the nature of the infection.” In his
Entitlement Decision, Chief Special Master Corcoran found that not only is there
“incontrovertible evidence that Petitioner first experienced URI symptoms before
neurologic-related symptoms, but also that the majority of [petitioner’s] treaters deemed
the URI most likely causal. The vaccine does not deserve greater weight simply
because it is ‘known’ whereas the precise nature of the infection is not.” (emphasis in
original; alteration added). In his Entitlement Decision, Chief Special Master Corcoran,
citing Randolph v. Secretary of Health & Human Services, No. 15-146V, 2021 WL
5816271, at *21 (Fed. Cl. Spec. Mstr. Nov. 12, 2021), indicated that “medical science
cannot always test for or identify a specific infection.” According to Chief Special Master
Corcoran,

       [t]here are circumstances where experts on both sides concede two or
       more factors could be causal of injury (including vaccination), resulting in
       entitlement for the petitioner if the special master concludes that the
       vaccine was at least a ‘substantial’ factor (even if not the primary or
       predominant factor). Deribeaux v. Sec’y of Health & Hum. Servs., 105
       Fed. Cl. 583, 589 (June 4, 2012). But here, there was no concession by
       Dr. Collins that the Tdap vaccine can be causal at all—and I have found
       that Petitioner did not preponderantly establish this to the case. Thus, the
       mere fact that temporarily [sic] Petitioner received the Tdap vaccine before
       onset of his URI does not compel me into a Shyface determination that the
       URI was not likely solely causal.
(emphasis in original; alteration added). In fact, in her January 23, 2020 expert report,
Dr. Collins stated,
       [t]he timing of [K.A.]’s symptoms in relationship to the Tdap vaccine is
       most likely coincidental. An influenza-like illness that followed the vaccine
       and preceded development of GBS is more likely than not the cause of
       [K.A.]’s GBS. There is no evidence that aluminum in the Tdap vaccination
       causes GBS, while conversely there is a known association between
       influenza-like infection and the development of GBS. Therefore, I do not
       believe the evidence in this case is supportive of the conclusion that the
       Tdap vaccine caused or substantially contributed to [K.A.]’s symptoms.
(alteration added).
      After examining petitioner’s medical records and all the expert reports, Chief
Special Master Corcoran found that
       [p]etitioner has not preponderantly established that the Tdap vaccine can
       cause GBS, under either of the two causation theories ventured over the
       case’s six-year life—and even if he had, the record demonstrates it is far
                                            36
      more likely his GBS was attributable to an intercurrent upper respiratory
      infection (“URI”) than vaccination.
Chief Special Master Corcoran’s analysis and conclusions and rejection of the Torday
analysis as a basis for his Entitlement Decision was not arbitrary, capricious, or an
abuse of discretion, given the facts of petitioner’s medical records in the above
captioned case.

                                    CONCLUSION
       This court finds that Chief Special Master Corcoran’s examination of the record
before the court in petitioner’s case, including the multiple, albeit conflicting, expert
opinions by Dr. Steinman and Dr. Collins, petitioner’s contemporaneous medical
records and the literature submitted, resulted in a decision which was not “arbitrary,
capricious, an abuse of discretion, or otherwise not in accordance with law.” 42 U.S.C.
§ 300aa-12(e)(2)(B). The Chief Special Master’s Entitlement Decision is affirmed.
Petitioner’s Motion for Review is DENIED. The Clerk of the Court shall enter
JUDGMENT consistent with this Opinion.

      IT IS SO ORDERED.

                                                      s/Marian Blank Horn
                                                      MARIAN BLANK HORN
                                                               Judge

                                           37