The Role of Domestic Animals in the Epidemiology of Plague. II. Antibody to Yersinia pestis in Sera of Dogs and Cats

The sera of 1,556 dogs were collected in past and present foci of bubonic plague, in natural foci of plague where there were epizootics, and in plague-free areas. The sera were tested for antibody to the specific Fraction I antigen of Yersinia pestis (formerly known as Pasteurella pestis). Serologic evidence of plague infection was noted in 21.6% of the sera collected from dogs in bacteriologically proven foci of plague. Over 99.9^o of the canine sera collected in areas considered to be free of plague were negative for antibody to Y. pestis. The results indicate that the testing of canine sera for antibody to Y. pestis is one of the most expeditious methods available for the detection of foci of plague. The relation of the dog to man and the dog's rapid serologic response to the plague bacillus suggest that these animals could serve as useful amplifiers and/or sentinel animals for the detection of plague in areas frequented by man.