Decode the disappearance of leprosy in Europe

Scientists believe they are getting closer to solving the mystery why leprosy (or leprosy) disease suddenly disappears in Europe 500 years ago.

The leprosy was one of the most feared "assassins" across Europe with the victims being kicked out of towns and villages. The disease still exists in 91 countries around the world and attacks about 225,000 people a year, but in Europe it suddenly declined in the 16th century.

One of the most popular hypotheses about the reason for this gradual disappearance is that the pathogen has evolved and lost its deadly toxicity. However, scientists can now reject this hypothesis after discovering that today's "culprit" of leprosy in the Middle East and some other parts of the world is almost identical to the pathogen in Medieval Europe.

The leprosy that caused pandemics raged throughout medieval Europe.(Photo: Shutterstock)

The findings came after researchers analyzed the genes of Mycobacterium leprae , the leper culprit, taken from medieval bone samples in England, Sweden and Denmark. It implies that Europeans have developed a natural antibody that helps fight disease.

In an article published in Science, a group of international researchers concluded: "The sudden decline of leprosy in Europe in the 16th century is almost certainly not caused by the M. leprae strain in this continent. the loss of the deadly poison external factors, such as other infectious diseases such as tuberculosis, changes in host immunity or improved social conditions can lead to this recession ".

Of the 3.3 million chemical characters discovered in the genome of modern-day pathogens, only 20 are different from their medieval versions, according to Dr. Johannes Krause, a Dai geneticist. Study Tuebingen (Germany).

Dr. Stewart Cole, director of the Institute of Global Health in Switzerland, adds that the new hypothesis seems reasonable because some other studies have identified genetic factors that make most Europeans resistant. leprosy is better than most people in other parts of the world.

However, Mr. Cole added: "We currently have no data to determine the direction of the leprosy epidemic. The pathogen may have been taken to Palestine during Crusades (the religious war to serve. in the Christian control of the Holy Land - pv. However, this process can also happen in the opposite direction. "

Leprosy (leprosy, leprosy) is not a genetic disease but a bacterial infection , caused by a bacillus called Mycobacterium leprae (also known as Hansen bacillus ). This disease is spread by skin or respiratory. However, whether or not the disease depends on the body's response to M. leprae.

Leprosy mainly affects the skin and peripheral nerves. The disease is not lethal but can cause disability, there are two types as follows: Bacterial disability directly infects nerves, resulting in loss or loss of feeling, muscle paralysis, muscle atrophy, contraction of the finger, puffy feet, rabbit eyes, bone resorption, reduced sweating; Disability caused by patients who are not educated, do not know how to take care of their hands and feet without feeling, do not know how to take care of skin wounds and lead to osteoarthritis.