Black Rats

The black rat, also called the roof rat, is the primary host for bubonic plague, which is transmitted to humans by direct contact or through the bites of fleas that have fed on infected rats. The black rat is believed to have come originally from southern or southeastern Asia. Although the first written record of it in Europe was not until the 1200s, a 1979 announcement of the discovery in a sealed well of the bones of two black rats, radiocarbon-dated to about the 4th century, places the black rat in Britain hundreds of years before the plagues there of the 6th and 7th centuries.