Epidemiologic characteristics of rabies virus variants in dogs and cats in the United States, 1999

Abstract

Objective: To evaluate epidemiologic features of rabies virus variants in dogs and cats in the United States during 1999 and assess the role of bat-associated variants.

Design: Epidemiologic survey.

Sample population: Rabies viruses from 78 dogs and 230 cats.

Procedure: Brain specimens from rabid dogs and cats were submitted for typing of rabies virus. Historical information, including ownership and vaccination status, was obtained for each animal. Specimens were typed by use of indirect fluorescent antibody assay or reverse transcriptase polymerase chain reaction assay and nucleotide sequence analysis.

Results: Nearly all animals were infected with the predicted terrestrial rabies virus variant associated with the geographic location of the submission. A bat-associated variant of rabies virus was found in a single cat from Maryland. More than half (53%) of submitted animals were classified as owned animals, and most had no known history of vaccination. One vaccination failure was reported in a dog that did not receive a booster dose of rabies vaccine after exposure to a possibly rabid animal.

Conclusions and clinical relevance: Bat-associated rabies virus variants were not a common cause of rabies in dogs and cats during 1999. Vaccine failures were uncommon during the study period. Because most rabid dogs and cats were unvaccinated and were owned animals rather than strays, educational campaigns targeting owners may be useful.