Some people think of rats as ugly vermin that infest the streets. Others see them as intelligent creatures that are tested in science labs. Yet others see them as cute, cuddly little pets. But did you know that rats were the messengers of doom in the 1320’s because they carried the Black Plague?

The Plague started in Mongolia. The reason it started was a germ called "Yersina Pestas", which infected the rats. There are several different kinds of Black Plague. The most widely known kind is the Bubonic Plague, which is spread by fleas. When all the rats started dying, their fleas moved to humans, and started killing the Mongolians, who fled. It was the year 1320, and people brought messages and the plague with them. Soon the plague had spread all over China and Mongolia. It spread westward in caravans from India to Europe. The roadsides were covered in dead bodies.

The Pope was told by most people to flee, but his doctor told him to have little or no contact with other humans and sit by the fire. That remedy worked, and the pope survived. In Florence, three-fourths of the population died. An English monk named Robert of Avesbury wrote, "the plague passed most swiftly, killing at midday those who had been well in the morning." Norwich was an example. It had a population of 70,000, but when the plague finished, only 6,628 people were left alive! The Black Plague is considered the worst plague ever.

Nursery Rhymes often talk of things happening to people at the time a rhyme is written. One rhyme you have probably heard is “Ring Around the Rosie”. It is rumored to have originated during the plague. The second line that sings “Pocket full of posies” was thought to refer to herbs people carried around to heal themselves. Because of that line, the rhyme got the bad reputation of starting during the plague. However, the author of the Annotated Mother Goose, a book about nursery rhymes, says that the first time “Ring around the Rosie” was published was 1881. That was much later than the plague! This goes to show that you should always look for the truth about rumors before you blame them on rats!

For more on rats and the Black Death:

Discovery Online Stories - The Black Death
New England College Lecture on the Black Death
BBC Education on the Black Death
History Magazine - The Black Death
Black Death - a Biological Perspective (Experiment)