Kelley Kaczerowski v. HHS - Tdap, Guillain-Barré syndrome (2025)

Kelley Kaczerowski, a 31-year-old pregnant woman, received a Tdap vaccine on July 25, 2019. Approximately 28 days later, she developed symptoms consistent with Guillain-Barré syndrome (GBS), including weakness, numbness, and tingling in her extremities.

She had a history of lupus and psoriasis. Petitioner argued that the Tdap vaccine caused her GBS through molecular mimicry, presenting expert testimony from Dr.

Carlo Tornatore. Respondent, the Secretary of Health and Human Services, contested this, presenting expert testimony from Dr.

Marcela Pasetti and Dr. Dara Jamieson, who argued that the scientific evidence did not support a causal link between the Tdap vaccine and GBS.

They highlighted the lack of specific evidence for molecular mimicry with Tdap components, the unreliability of case reports, and the strength of epidemiological studies showing no association. The court reviewed the medical records, expert reports, and scientific literature.

Ultimately, the Chief Special Master found that Petitioner failed to establish by a preponderance of the evidence that the Tdap vaccine can cause GBS or that it did cause her specific injury. The court noted deficiencies in the molecular mimicry theory, the limited value of case reports, and the lack of strong epidemiological support for a Tdap-GBS link.

The court also found that Petitioner's initial symptoms were more indicative of an infection than GBS onset and that her pregnancy did not necessarily make her more susceptible to a vaccine-induced autoimmune response. Therefore, entitlement to compensation was denied.