Filed under: Infectious Diseases
Plague was known as the Black Death during medieval times, when it killed up to a third of the population of Europe. Currently, plague occurs in fewer than 3,000 people per year worldwide. It can be deadly if not treated promptly with antibiotics.
The organism that causes plague, Yersinia pestis, lives in a variety of small rodents on every continent except Australia. The organism is transmitted to humans when they are bitten by fleas that have previously fed on infected rodents.
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.
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