Amy Mehl v. HHS - Tdap, rheumatoid arthritis (2025)

Amy Mehl filed a petition alleging that her Tdap vaccination on September 12, 2016, accelerated the onset of her rheumatoid arthritis (RA) by 2.5 years. She also received a flu vaccine on September 28, 2016, but her claim focused on the Tdap vaccine.

Ms. Mehl had a complex medical history including migraines, chronic Epstein Barr Virus (EBV), and significant back pain from a prior car accident.

Her medical records showed she tested positive for anti-CCP antibodies in 2014, indicating she was in the preclinical stage of RA. She also had a history of joint pain and stiffness prior to the Tdap vaccination.

Petitioner's expert, Dr. Gershwin, opined that the Tdap vaccine acted as the final trigger, accelerating her transition from preclinical to clinical RA by 2.5 years, citing the induction of proinflammatory cytokines.

Respondent's expert, Dr. Matloubian, disagreed, stating that the cause of RA is unknown, and there is no evidence that vaccines can trigger or accelerate its onset.

Dr. Matloubian emphasized that Ms.

Mehl's anti-CCP positivity in 2014 meant her RA was already developing years before the vaccination, and that chronic factors like smoking and microbiome changes are more likely contributors than acute events like vaccination. The court found that Ms.

Mehl failed to establish a sound medical theory under the first Althen prong, as Dr. Gershwin's opinion was speculative and lacked support in the literature, particularly regarding the role of vaccines in RA pathogenesis.

Furthermore, the court found no logical sequence of cause and effect under the second prong, noting that Ms. Mehl's prior history of joint pain and stiffness, along with the transient nature of her post-vaccination inflammatory markers, did not support Dr.

Gershwin's theory. Finally, under the third prong, the court found no medically acceptable timeframe for inferring causation, as the onset of clinical RA was not clearly linked to the vaccination.

The court concluded that Ms. Mehl did not prove by a preponderance of the evidence that the Tdap vaccine caused or accelerated her RA and therefore denied her claim.