Incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets.

OBJECTIVE

To determine incidence of and risk factors for adverse events associated with distemper and rabies vaccine administration in ferrets.

DESIGN

Retrospective cohort study.

ANIMALS

3,587 ferrets that received a rabies or distemper vaccine between January 1, 2002, and December 31, 2003.

PROCEDURES

Electronic medical records were searched for possible vaccine-associated adverse events. Adverse events were classified by attending veterinarians as nonspecific vaccine reactions, allergic reactions, or anaphylaxis. Patient information that was collected included age, weight, sex, cumulative number of distemper and rabies vaccinations received, clinical signs, and treatment. The association between potential risk factors and occurrence of an adverse event was estimated with logistic regression.

RESULTS

30 adverse events were recorded. The adverse event incidence rates for administration of rabies vaccine alone, distemper vaccine alone, and rabies and distemper vaccines together were 0.51%, 1.00%, and 0.85%, respectively. These rates were not significantly different. All adverse events occurred immediately following vaccine administration and most commonly consisted of vomiting and diarrhea (52%) or vomiting alone (31%). Age, sex, and body weight were not significantly associated with occurrence of adverse events, but adverse event incidence rate increased as the cumulative number of distemper or rabies vaccinations received increased. In multivariate logistic regression analysis, only the cumulative number of distemper vaccinations received was significantly associated with the occurrence of an adverse event.

CONCLUSIONS AND CLINICAL RELEVANCE

Results suggest that in ferrets, the risk of vaccine-associated adverse events was primarily associated with an increase in the number of distemper vaccinations.