“Black death” remains the most fatal pandemic in the history of mankind. He exterminated up to half the population of Europe, Western Asia and Africa, killing tens of millions.
“Black death” is the most deadly photo pandemic: Shuterstock
The mystery of “black death” was finally resolved. Research has shown that the evolution of a single gene at Yersinia Pestis, the bacterium that causes the bubonic plague, allowed it to adapt and survive so long, according to Dailymail.
The study addresses key questions about how pandemic penetrates into human populations, causes huge diseases and evolves at different levels of virulence. In the future, discoveries could help us prevent another pandemic.
“This is one of the first research studies that directly examine the changes of an ancient pathogen, which we encounter today, in an attempt to understand what determines the virulence, persistence and/or possible extinction of PandemiiloR ”, said the main co -author, Professor Hendrik Painar
The new study was conducted by researchers at McMaster University in Canada and the Pasteur Institute in France.
The bacteria that cause the plague have evolved to become less lethal over time, allowing them to continue to infect people in three separated pandemics over more than a thousand years, their research revealed.
The “black death” began in the mid -300s and was the most deadly pandemic in the history of mankind, killing up to half the population of Europe, Western Asia and Africa, the epidemics continuing for centuries.
The third pandemic of bubonic plague broke out in China in the 1850s and continues today, some cases being still registered in some parts of Subsaharian Africa.
“The plague bacteria are of particular importance in the history of humanity, so it is important to know how these epidemics have spread.”said Javier Pizarro-Ciderda, co-author of the study.
A bacterium has extended the duration of the pandemi
According to the quoted publication, the researchers examined the samples of Yersinia Pestis, the bacteria that causes the plague, dating from each pandemic. In all three cases, the genes of each bacteria of the plague have evolved to become less virulent and less deadly, according to the study, causing less serious infections. It is believed that the bacteria has extended the duration of the pandemic, because it has achieved more opportunities to spread between people.
The researchers confirmed this theory by infecting rats with recent plague samples, showing that the disease lasted longer when the virulence decreased.
While antibiotics can now effectively fight the plague, research could bring to light how other pandemic can evolve.
“This allows us to obtain a comprehensive understanding of how pathogens can adapt to different situations. Finally, we better understand what the plague is and how we can develop measures to defend us,” said Pizarro-Center.
The “black death” of 1348 killed half of the population of London in 18 months, the bodies being piled up in common pits at five depths.
When he hit the great plague of 1665, one fifth of the inhabitants of London died, the victims being closed in their homes and with a red cross painted on the door with the words “May the Lord have mercy on us.”
The pandemic spread in Europe between the fourteenth and 19th centuries-it is believed to have been caused by fleas that feed on infected rats before biting people and transmitting their bacteria.
