Angela Hiatt v. HHS - Tdap, Guillain-Barre syndrome (GBS) (2026)
Case summary [AI summaries can sometimes make mistakes]
On September 6, 2019, Angela Hiatt filed a petition seeking compensation under the National Vaccine Injury Compensation Program, alleging that she developed Guillain-Barré syndrome (GBS) as a result of receiving the tetanus-diphtheria-acellular-pertussis (Tdap) and human papillomavirus (HPV) vaccines on February 16, 2017. Petitioner later narrowed her claim to focus solely on the Tdap vaccine.
Ms. Hiatt, who was 45 years old at the time of vaccination, experienced no immediate adverse reaction.
Eleven days post-vaccination, on February 27, 2017, she presented to an emergency department with chest and back pain, which was attributed to non-cardiac causes. She also reported upper respiratory symptoms.
Over the next few days, her symptoms progressed to include weakness and numbness, and she reported a preceding gastrointestinal illness. She was hospitalized and diagnosed with GBS, characterized by absent reflexes and elevated cerebrospinal fluid protein.
Ms. Hiatt required intensive care, intubation, and intravenous immunoglobulin (IVIG) treatment, followed by rehabilitation.
She gradually improved but continued to experience residual neurologic sequelae. Petitioner presented expert testimony from Dr.
Carlo Tornatore, a neurologist, who opined that the Tdap vaccine could trigger GBS through molecular mimicry, citing homology between tetanus toxin and nerve myelin components, and referencing government publications that advised caution with tetanus-containing vaccines in individuals with a history of GBS. Respondent presented expert testimony from Dr.
Kourosh Rezania and Dr. Olajumoke Fadugba, both neurologists.
Dr. Rezania conceded the GBS diagnosis but attributed its onset to a possible prior infection, doubting the Tdap vaccine's causal role due to the low risk and questioning the probative value of cited literature.
Dr. Fadugba also emphasized GBS as typically post-infectious, found the evidence for a Tdap-GBS association weak, and argued that molecular mimicry was not sufficiently demonstrated for the Tdap vaccine.
The Special Master, Brian H. Corcoran, denied entitlement, finding that Petitioner failed to establish by a preponderance of the evidence that the Tdap vaccine can cause GBS or did so in her case.
The Special Master found Dr. Tornatore's theory to have substantive deficiencies, noting that evidence supporting the flu vaccine's link to GBS was not directly applicable to Tdap, that wild-analogs of Tdap components were not shown to be associated with GBS, that passive surveillance data and case reports were weak proof of causation, that existing epidemiologic evidence suggested no likely association, and that homology showings were speculative.
The Special Master also found that government precautions regarding tetanus vaccines and GBS were inapplicable to Ms. Hiatt as she had no prior history of GBS after a Tdap vaccine.
On review, the United States Court of Federal Claims, in an opinion by Judge David A. Tapp, affirmed the Special Master's decision.
The Court found no legal error and that the Special Master applied the correct preponderance of the evidence standard, not requiring scientific certainty. The Court determined that the Special Master's factual findings were not arbitrary or capricious and that the petitioner's arguments regarding the interpretation of government warnings and the burden of proof were unavailing.
The case was ultimately denied.
Theory of causation
Tdap and HPV vaccines on February 16, 2017, age 45, alleged to cause Guillain-Barre syndrome; the claim was narrowed principally to Tdap. DENIED. Petitioner relied on Dr. Carlo Tornatore and molecular mimicry/immune-mediated theory. Respondent contested diagnosis, theory, and case-specific causation. Special Master Gowen denied entitlement on October 24, 2025. Judge Carolyn N. Lerner denied petitioner's motion for review and sustained the decision on February 5, 2026; public reissue March 2, 2026 had no redactions.