In five years, Black Death wiped out an estimated 30 to 50 percent of Europe's population. This medieval plague was caused by the bacterium Yersinia pestis , which still circulates among humans .
Read More »In five years, Black Death wiped out an estimated 30 to 50 percent of Europe's population. This medieval plague was caused by the bacterium Yersinia pestis , which still circulates among humans .
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