Prevalence of antibodies against Yersinia pestis in domestic carnivores, in plague foci in the State of Ceará

The prevalence of antibodies against Yersinia pestis in domestic carnivores (dogs and cats), in plague areas in the State of Ceará, was analyzed to establish the importance of monitoring these animals within the routine practice of the plague control program. Over the decade 1997-2006, 146,732 serum samples were examined (95,883 from dogs and 50,849 from cats), of which 2,629 (2,234 from dogs and 395 from cats) proved to be positive. The prevalence among dogs (85%) was higher than among cats (15%) throughout the decade and in all places, except in Ibiapina in 1998. The significance of these findings has not yet been determined. Studies on this zoonosis in Brazil have been based on paradigms that did not cover all the elements involved in the zoonosis, thus making it impossible to properly understand the role of these carnivores. Monitoring of plague foci conducted exclusively by means of dog surveys may result in progressive lack of knowledge of the epidemiological situation of plague, if supplementary inter-institutional research is not developed.