Stop blaming rats for the Black Death—humans may have spread the plague

black rat th century engraving spl

Rats were not to blame for the spread of plague during the Black Death, according to a study. The rodents and their fleas were thought to have spread a series of outbreaks in 14th-19th Century Europe.

But a team from the universities of Oslo and Ferrara now says the first, the Black Death, can be “largely ascribed to human fleas and body lice”. The study, in the Proceedings of the National Academy of Science, uses records of its pattern and scale.

…

“We have good mortality data from outbreaks in nine cities in Europe,” Prof Nils Stenseth, from the University of Oslo, told BBC News.

“So we could construct models of the disease dynamics [there].”

He and his colleagues then simulated disease outbreaks in each of these cities, creating three models where the disease was spread by:

  • rats
  • airborne transmission
  • fleas and lice that live on humans and their clothes

In seven out of the nine cities studied, the “human parasite model” was a much better match for the pattern of the outbreak. It mirrored how quickly it spread and how many people it affected.

“The conclusion was very clear,” said Prof Stenseth. “The lice model fits best.”

…

“Our study suggests that to prevent future spread hygiene is most important,” said Prof Stenseth.

Read full, original post: Black Death ‘spread by humans not rats’

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