TDaP Reaction: Causation in Fact Claim
Jump v. HHS, Case No. 11-301V (Fla. Spec. Mstr. Aug. 31, 2015) (Hamilton-Fieldman, SM)
In this case, experts for both sides agreed that Petitioner was more likely than not in the “preclinical stage” of Rheumatoid Arthritis at the time of her TDaP vaccine, potentially raising the issue of significant aggravation. However, the special master, analyzing the SOL provision of the Vaccine Act, noted that the application of the Act is triggered by “the first symptom or manifestation of onset” of an alleged vaccine-related injury, and since Petitioner was asymptomatic at the time of the vaccine, the claim should be analyzed as a causation in fact claim and not significant aggravation.
Petitioner’s expert testified that an individual with preclinical RA “is at increased risk to develop overt disease if they encounter an environmental trigger such as an infection, vaccination, ultraviolet radiation, or certain chemicals.” Further, because Petitioner already suffered from several other preexisting inflammatory conditions, she was at increased risk to develop another inflammatory condition like RA following vaccination. The medical theory presented was that the abrupt onset of severe disease would be consistent with his theory that the introduction of an antigen to an individual with a predisposed, hyperactive immune system can trigger an immune complex-mediated inflammatory response from existing B and T lymphocytes, in a typical window of 6-21 days.
Respondent’s expert testified that no environmental trigger is needed to prompt the onset of RA in a patient with overlap syndrome or preclinical RA. She also noted that the IOM report concluded that there was not enough evidence to accept or reject a causal relationship between Tdap and the development of RA. The special master observed that the IOM report “cannot show that the vaccine cannot cause that particular injury” in the prong 1 analysis. This was especially true in a case where the medical theory was premised on the vaccinee having a compromised immune system. Well-done epidemiological studies typically exclude patients with immune system abnormalities.
With regard to prong 1, the special master concluded that although an environmental trigger is not required to transform preclinical RA to RA, the facts of the case, an acute and severe onset of an otherwise chronic condition, made the medical theory sufficiently persuasive. The special master rejected Respondent’s expert testimony on prong 2, that Petitioner was already suffering overtly from RA at the time of the vaccine. On the issue of timing, the special master gave more weight to the approach taken by Petitioner’s expert, which focused on contemporaneous evidence, rather than the recollections of the Petitioner which Respondent’s expert relied upon.