Yersinia pestis is a flea-borne bacterium that causes plague, which is maintained among rodent hosts and their fleas, but spillover into accidental hosts can result in the geographic spread of the disease.
Domestic cats are a major source of human plague infections in the United States, putting veterinary workers and pet owners at risk for Y. pestis infections. Twelve cases of plague transmission from nondomestic carnivores to humans have been documented, including a fatal case of human pneumonic plague in 2007 that resulted from direct contact with an infected puma (Puma concolor).
Pumas and bobcats (Lynx rufus) are two of the most widespread felids in North America, with pumas having the greatest range of any wild terrestrial mammal in the Western Hemisphere. Both species inhabit large territories and travel great distances during dispersal. These highly mobile animals may periodically reintroduce Y. pestis-positive fleas to distant regions, especially during epizootics (outbreaks in a particular geographic area). Consequently, carnivore-aided flea dispersal could play an important role in the spread and persistence of plague during inter-epizootic periods.
Puma and bobcat data from this study collected in California and Colorado suggest exposure to Y. pestis followed by recovery. All animals were outwardly healthy. Deaths caused by plague have been documented in wild felids and the potential for plague exposure remains a concern for field biologists, veterinarians, hunters, and skinners. Field biosafety guidelines have been developed in conjunction with Colorado State University’s Biosafety Office as a result of these findings. Recommendations include wearing disposable gloves, long pants, and long-sleeved shirts when handling anesthetized animals and using an N95-rated mask when conducting necropsies or handling deceased animals. Outside of human infections, plague could constitute a problem for felid conservation in areas of high plague activity.
Results suggest large numbers of Y. pestis–exposed pumas and bobcats. High regional testing indicates these animals may be involved in the persistence and transmission of Y. pestis. This and the documented transmission of plague from nondomestic carnivores to humans emphasize the need to better understand the role of wild felids in plague dynamics.
Bevins SN, Tracey JA, Franklin SP, Schmit VL, MacMillan ML, Gage KL, et al. Wild felids as hosts for human plague, western United States. Emerg Infect Dis [serial on the Internet]. 2009 Dec [date cited]. Available from http://www.cdc.gov/EID/content/15/12/2021.htm
Source: CDC Emerging Infectious Diseases Volume 15, Number 12–December 2009.