The Idaho Division of Public Health identified Yersinia pestis, the bacterium that causes plague, in six domestic cats in mid-2016.
The Centers for Disease Control and Prevention released notes on the cases in the Dec. 9 issue of the Morbidity and Mortality Weekly Report.
In 2015, Y pestis was identified in dead ground squirrels in Idaho. In mid-2016, Idaho veterinarians reported evaluating five dogs and 12 cats for possible plague. Y pestis was isolated from six cats.
Three cats were treated with antibiotics; two survived, and one was euthanized. The three other cats had died or been euthanized. According to the notes, “All six cats reportedly had contact with ground squirrels and other wild rodents or rabbits before becoming ill.”
No human cases of plague were reported. According to the notes, “Cat-associated human plague cases, including fatalities, have been reported in the western United States since 1977.”
Also according to the notes: “Veterinarians should consider the diagnosis of plague in pets, including cats, with compatible signs and exposure to rodent habitats, rodents, or ill pets in areas where plague is endemic or epizootic. Suspicion of plague should trigger the following actions by veterinary staff: 1) implementation of personal protective measures, including wearing masks and gloves; 2) isolation of the ill pet; 3) assessment of pulmonary involvement; 4) initiation of diagnostic testing for Y pestis; 5) prompt administration of antibiotic therapy; 6) implementation of flea control for affected animals and the hospital environment; 7) provision of advice on household flea control to pet owner; and 8) notification of public health officials.”
The notes state that cats infected with Y pestis usually develop fever, anorexia, lethargy, and lymphadenitis. Approximately 10 percent of infected cats are pneumonic.