The bubonic plague, a bacterial infection spread by fleas that live on rodents, is a serious disease that can be fatal if not treated promptly. The plague is still found in some parts of the world today, so it is important to be aware of the symptoms and know how to avoid infection.
The bubonic plague is caused by the bacterium Yersinia pestis. The bacteria are typically transmitted to humans through the bite of an infected flea. The fleas become infected when they feed on rodents that are carrying the plague bacteria.