In this study, computerized medical records of 375 primary care clinics in 41 states were searched for evidence of adverse reactions to vaccine in ferrets. During a 2-year period, over 9000 office visits involving ferrets were identified and 3500 (38%) involved the administration of distemper and/or rabies vaccine (4995 vaccine doses were administered). Thirty vaccine reactions (mostly vomiting and diarrhea or vomiting alone) were identified. All adverse reactions occurred immediately after vaccination. None of the ferrets died. Treatments included dexamethasone, diphenhydramine, and oxygen. Age, sex, and body weight were not associated with increased risk for adverse reactions. However, risk did increase along with the number of vaccinations (rabies or distemper).
COMMENTARY: The estimated risk for an adverse vaccine event in ferrets has been reported to be approximately 5%. In this study, risk was less than 1%. The most likely explanation for this marked difference is the "power of numbers." The 5% estimate was based on a small sample size. What is important in day-to-day practice is that the risk is relatively low and if there is an adverse reaction it will happen quickly and is unlikely to be fatal. The major predisposing factor to adverse events is the cumulative number of vaccinations.
Incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets. Moore GE, Glickman NW, Ward MP, et al. JAVMA 226:909-912, 2005.