Alex Ehsan, MD, PhD · Medical search

Plague

Educational information. Individual clinical review of this presentation by Dr. Ehsan is not yet documented. It does not replace personal medical evaluation.

Source: MedlinePlus, National Library of Medicine. Read the original source

MedlinePlus data edition September 26, 2026. Imported September 27, 2026. These dates do not indicate a new clinical review of the article.

Plague is an infection caused by the bacterium Yersinia pestis. The bacteria are found mainly in rats and in the fleas that feed on them. People and other animals can get plague from rat or flea bites. In the past, plague destroyed entire civilizations. Today plague is uncommon, due to better living conditions and antibiotics.

There are three forms of plague:

Lab tests can diagnose plague. Treatment is a strong antibiotic. There is no vaccine.

Questions for your care team

General prompts to help prepare for your appointment.

For a life-threatening emergency, call 911 in the U.S. or your local emergency number.

Browse all patient guides