Pets such as cats and dogs also may get bubonic plague. They usually become infected from touching, biting, or eating an infected mouse or rat. If the infected cat or dog has fleas, those fleas can give the plague bacteria to people through bites. People can also become infected by touching the infected skin or fluids of the dog or cat.
During the Middle Ages, bubonic plague was known as the "Black Death." During that time many people became sick with pneumonia from Yersinia pestis (called "pneumonic plague") and spread the disease bacteria to each other by coughing and sneezing.