Heather Peterson v. HHS - Influenza, transverse myelitis / clinically isolated syndrome evolving to multiple sclerosis (2025)

Heather Peterson, a 32-year-old adult, received an influenza vaccine on March 26, 2019. She alleged that this vaccine caused her to develop transverse myelitis (TM), which later evolved into multiple sclerosis (MS).

Initially, Peterson experienced numbness and tingling three days after vaccination, leading to medical visits and a diagnosis of TM or clinically isolated syndrome (CIS) in April 2019. However, subsequent medical evaluations and MRIs indicated the development of MS, a chronic and relapsing demyelinating disease of the central nervous system.

The court considered expert opinions from both sides. Petitioner's expert, Dr.

Carlo Tornatore, argued for a causal link based on molecular mimicry and the possibility of vaccines triggering autoimmune responses, suggesting the flu vaccine could cause TM, which in turn could lead to MS. Respondent's expert, Dr.

Subramaniam Sriram, contended that MS is not typically caused by vaccines, that the scientific literature does not support such a link, and that Peterson's initial symptoms were likely the first manifestation of pre-existing MS, not a vaccine-induced injury. The court found that MS is a distinct condition from TM and is not understood to be caused by vaccines in the same way acute demyelinating injuries might be.

The court also noted that Peterson's initial symptoms appeared too soon after vaccination for an antibody-driven process and that evidence suggested her MS might have predated the vaccination. Ultimately, the court denied entitlement, finding that Peterson failed to establish by a preponderance of the evidence that the flu vaccine could cause MS or did so in her case, and that her initial TM-like symptoms were part of the MS disease process, not a separate vaccine-induced injury.