The Role of Domestic Animals in the Epidemiology of Plague. I. Experimental Infection of Dogs and Cats

Abstract

Dogs and cats are susceptible to experimental plague. Both species demonstrate bacteremia due to Yersinia pestis, formerly known as Pasturella pestis, as a result of the infection and thus may serve as the source of an infectious blood meal for fleas. The suppurating lesions developed by the cat indicate that there may be some risk of mechanical plague infection for those handling such animals. Despite this, the risk of infection of human beings due to contact with cats and dogs infected with plague is considered minimal. For the first time it has been experimentally established that, irrespective of the mode of infection, cats and dogs develop antibodies of high titer to the specific Fraction I antigen of Y. pestis. Such antibodies persist for at least 300 days in the sera of cats and dogs. The frequency with which such specific antibodies to Y. pestis can be detected in the sera of dogs that live in epidemic and natural plague foci indicates that serologic tests of canine sera for antibody to the plague bacterium should be an integral part of every survey and surveillance program.