Plague has been identified as a disease of concern to human, wildlife and domestic animal populations within the United States. It is also considered a "Category A" disease by the Department of Homeland Security, meaning it could potentially be used as a bioterrorist agent.
Members of the cat family, Felidae, such as bobcats, mountain lions and domestic cats are particularly susceptible to plague while the Canidae (dog) family, including coyotes, wolves and domestic dogs, tend to be fairly resistant to plague. Because cats are susceptible to plague and tend to develop the highly-contagious form of the disease (pneumonic plague), they can represent a health threat to people who come in contact with them (ie, sportsmen, wildlife personnel & pet owners). While canids do not tend to develop an active form of plague, they do readily develop antibodies to plague when they come in contact with the disease through scavenging or predation of infected rodents. Testing the canid's blood for the presence of these antibodies is a convenient and efficient method of monitoring the area's rodent population for plague activity.
When the presence of plague is detected through lab diagnostic testing, this evidence is shared with local health officials, both human and veterinarian. Once alerted to the presence of the disease in their area, health personnel can be on the look-out for patients exhibiting plague's flu-like symptoms (fever, chills, swollen lymph nodes, etc.). Plague symptoms so closely resemble other common diseases that physicians and verterinarians who have not been alerted that plague is active in their area may fail to consider plague in their diagnostic testing. Because plague is generally not a commonly-encountered disease, health providers who are unaware of its presence are likely to only test for the more commonly-encountered illnesses, thus delaying the true diagnosis. When detected early, plague infections can be readily treated with antibiotic drugs with excellent results. A delay in the diagnosis, even for a short period, can make treatment much more difficult and could lead to fatal illness.
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