A new study suggests that the plague, which killed millions of people, was not transmitted by rats.

Nearly four dozen people have died.

A Northwestern University plague researcher has been charged with a brutal murder. Here’s what we know about him.

Plague-causing bacteria may have been around as early as 5,000 years ago, though a genomic analysis suggests that ancient strains were less contagious.

Pneumonic plague last month claimed 10 lives in 13 days, the World Health Organization reports.

Researchers find Oriental rat fleas, the insects that can carry plague bacteria, on New York City-dwelling rodents.

Ancient skeletons test positive for plague-causing bacteria.

A controversial Boston University laboratory could open by the end of the month, but at a lower safety rating than originally planned.