Objective: To identify common elements of large-scale human exposures to rabid or presumed rabid animals in the United States from 1990 to 1996.
Design: Retrospective study.
Procedure: Health departments in 50 states and the District of Columbia were contacted regarding episodes of large-scale human exposures to rabid animals occurring between 1990 and 1996. A large-scale exposure was defined as administration of postexposure prophylaxis (PEP) to 25 or more people after an exposure to a rabid or presumed rabid animal or littermates. Incident-specific information was obtained through questionnaires sent to states reporting episodes. Data are reported as medians.
Results: Fifteen of 51 (29.4%) health departments reported 22 episodes; 72.7% involved companion animals or livestock. Twenty-six animals were involved in these 22 episodes, including 10 (38.5%) dogs, 4 (15.4%) livestock, 4 (15.4%) raccoons, 3 (11.5%) cats, 3 (11.5%) bats, and 2 (7.7%) ferrets. Schools (36.4%) and public places (22.7%) were the most common settings for exposures. Reportedly, 1,908 people received PEP. The cost for 10 episodes was $61,547/episode (range, $14,199 to $1,500,000). An episode-specific written algorithm for recommending PEP had been developed for use in only 4 (18.2%) episodes.
Clinical implications: Large-scale exposures most commonly involved a single companion animal. Exposures attributable to improper handling of wildlife and unrestricted access of animals in schools and public areas can be potentially remedied by targeted education. Use of an episode-specific algorithm to determine need for PEP may also reduce the number of unnecessary treatments.