Minor changes turned Black Death germ from mild to murderous

WASHINGTON (Reuters) - The bacterium Yersinia pestis has inflicted almost unimaginable misery upon humankind over the centuries, killing an estimated 200 million or more people and triggering horrific plagues in the 6th and 14th centuries.

Source: Reuters: Health - June 30, 2015 Category: Consumer Health News Tags: healthNews Source Type: news