Plague
Plague is transmitted by fleas that become infected with the bacteria Yersinia pestis that cause plague. About 14% (1 in 7) of all plague cases in the United States are fatal. Human plague in the United States has occurred as mostly scattered cases in rural areas (an average of 10 to 20 persons each year). Globally, the World Health Organization reports 1,000 to 3,000 cases of plague every year. It is possible to get plague from a person infected with plague when the infected person has plague pneumonia and cough droplets containing the plague bacteria into air that is breathed by a non-infected person. The symptoms may include a swollen and very tender lymph gland, which is accompanied by pain. The swollen gland is called a "bubo" (hence the term "bubonic plague"). Bubonic plague should be suspected when a person develops a swollen gland, fever, chills, headache, and extreme exhaustion, and has a history of possible exposure to infected rodents, rabbits, or fleas.
A person usually becomes ill with bubonic plague 2 to 6 days after being infected. When bubonic plague is left untreated, plague bacteria invade the bloodstream. When plague bacteria multiply in the bloodstream, they spread rapidly throughout the body and cause a severe and often fatal condition. Infection of the lungs with the plague bacterium causes the pneumonic form of plague, a severe respiratory illness. The infected person may experience high fever, chills, cough, and breathing difficulty, and expel bloody sputum. If plague patients are not given specific antibiotic therapy, the disease can progress rapidly to death.
For more information, visit the Centers for Disease Control.