The bubonic plague is a very serious infectious disease caused by the bacterium Yersinia pestis. The plague is a zoonotic disease, which means it is usually transmitted to humans by animals. It is commonly transmitted through the bites of infected fleas or coming in direct contact with infected animal tissue (Schoenstadt, 2006). The bacterium can be found in fleas or small rodents such as chipmunks, squirrels, rats, or prairie dogs. The symptoms, including fever, chills, headache, and hemorrhages under the skin causing discoloration, are very harsh and unpleasant. This disease is infectious and extremely severe, and it is deadly if not treated properly and promptly (CDC, 2012).
Morin, Matthew and Westbrook, Ashton, "The Bubonic Plague" (2015). Infectious Diseases Project 2015. 6.