Model of bubonic plague bacteria - Smithsonian Museum of Natural History - 2012-05-17
A model of bubonic plague on display at the Smithsonian Museum of Natural History in Washington, D.C.
Bubonic plague is a bacterium known as "Yersinia pestis".
Bubonic plague kills two-thirds of its victims within four days. Outbreaks are rare, but at least 15 people get the disease every year in the United States; three or four die.
In 2003, the last year for which there is any data, nine countries reported bubonic plague outbreaks. More than 2,100 people became sick, and 182 died.