Scientists have found the oldest known evidence of the plague, which sparked deadly outbreaks dating back about 5,500 years ago — some 200 years earlier than previously thought.

Understanding the History of Plague

The disease has sickened humans for thousands of years and wiped out a significant chunk of Europe’s population in the 14th century during what’s known as the Black Death. Though rare, the plague is still around today and is treated with antibiotics.

Eske Willerslev, an evolutionary geneticist with the University of Copenhagen in Denmark, said, “To understand our own history, we believe that understanding the history of plague is extremely important.”

Willerslev and other researchers looked for traces of plague-causing bacteria in remains from four cemeteries near Siberia’s Lake Baikal. They found remnants of plague DNA in teeth from 18 ancient hunter-gatherers.

Dating the carbon in the bones revealed that the plague triggered two outbreaks, with the first cases detected around 5,500 years ago.

The team found that the prehistoric plague developed in stages and infected several small families. It likely spread from marmots — large native rodents — when people ate their raw organs or touched infected hides during butchery. The disease also traveled between people through coughing and sneezing.

Many of those who died were young children aged 8 to 11. Three young girls were buried side by side, two of whom were likely cousins. An aunt and nephew were found together, but her niece was in a different shared grave.

Researchers found that this type of ancient plague evolved long before bubonic plague, which was responsible for the Black Death that struck medieval Europe. But there’s evidence that earlier plagues were just as deadly. The disease decimated not only crowded cities, but also small, nomadic hunter-gatherer groups.

Original reporting: Texarkana Gazette — read the source article.