Leprosy was spread between humans and squirrels in the Middle Ages, study claims

Leprosy is one of the oldest infectious diseases recorded in humans, usually caused by the bacterium Mycobacterium leprae. Most of today’s cases occur in Southeast Asia and can be treated with antibiotics. In medieval England, this disease, known as leprosy and now known as Hansen’s disease, caused nausea and disfigurement in rich and poor people.

Early research revealed that people in medieval England, Denmark, and Germany had a similar strain of leprosy to the one found today in common squirrels elsewhere in England. One of the theories assumes that the disease could have been caused by a trade with squirrel dogs imported from Viking Scandinavia.

Genetic analysis has now revealed that squirrels in medieval England suffered from a very similar strain of the disease to humans in the 20th century.

It’s the first time we’ve found the remains of a leprosy host in archaeological finds, which is really exciting, said study co-author Sarah Inskipov from the University of Leicester, England. In the study together with his colleagues, he describes how they studied the strains of Hansen’s disease found in the samples of people who lived in Winchester between 900 and 600 years ago, and thus in the sample of the squirrel, whose bones they discovered in it for traces from about 1000 and 900 years ago.

That’s when he fell in love with Winchester, because in the center it was the place where there was a prison for lepers and countless carpenters who were engaged in the manufacture and sale of leather goods. The scientists extracted and analyzed the DNA from the samples and found that all of them had a very similar strain of leprosy.

In fact, the strains found in the remains of humans and squirrels from Winchester are not the strain found in medieval squirrels and the strain found in modern squirrels, Inskipov said.

According to the theme, the results indicate that there was a disease transmission between humans and squirrels. However, they are often based on only a few samples and thus cannot clarify whether people were originally infected with leprosy from squirrels or vice versa.

There are a number of possibilities as to how this could have happened. In addition to the trade in chickens, the breeding of squirrels could be called domestic squirrel breeding. Both mechanisms are mon. And don’t freak out, said Inskipov.

According to Inskip, the study also has consequences for people suffering from leprosy today. Maybe we should go and look at the spirits that move around these communities, she said, saying that they could spread the disease.