The Black Death may not have been spread by rats after all

The black rat, or ship rat, was thought to have helped transmit the Black Death Shutterstock / Carlos Aranguiz

The Black Death ravaged Europe between 1347 and 1353, killing millions. Plague outbreaks in Europe then continued until the 19th century.

One of the most commonly recited facts about plague in Europe was that it was spread by rats. In some parts of the world, the bacterium that causes plague, Yersinia pestis, maintains a long-term presence in wild rodents and their fleas. This is called an animal “reservoir”.