DefinitionBy Mayo Clinic staff
Plague is a serious bacterial infection that's transmitted by fleas. Known as the Black Death during medieval times, today plague occurs in fewer than 5,000 people a year worldwide. It can be deadly if not treated promptly with antibiotics.
The organism that causes plague, Yersinia pestis, lives in small rodents on every continent except Australia. The organism is transmitted to humans who are bitten by fleas that have fed on infected rodents or by humans handling infected animals.
The most common form of plague results in swollen and tender lymph nodes — called buboes — in the groin, armpits or neck. The rarest and deadliest form of plague affects the lungs, and it can be spread from person to person.
- Plague. Centers for Disease Control and Prevention. http://www.cdc.gov/plague/. Accessed Dec. 21, 2012.
- Longo DL, et al. Harrison's Online. 18th ed. New York, N.Y.: The McGraw-Hill Companies; 2012. http://www.accessmedicine.com/resourceTOC.aspx?resourceID=4. Accessed Dec. 21, 2012.
- Goldman L, et al. Cecil Medicine. 24th ed. Philadelphia, Pa.: Saunders Elsevier; 2012. http://www.mdconsult.com/das/book/body/191371208-2/0/1492/0.html#. Accessed Dec. 24, 2012.
- Sun W, et al. Developing live vaccines against Yersinia pestis. Journal of Infection in Developing Countries. 2011;5:614.
- Butler T. Plague into the 21st century. Clinical Infectious Diseases. 2009;49:736.
- Amedei A, et al. Role of immune response in Yersinia pestis infection. Journal of Infection in Developing Countries. 2011;5:628.
- FDA approves new antibacterial treatment for plague. FDA news release. http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/ucm302220.htm. Accessed Dec. 24, 2012.