Plague Was a Deadly Threat Thousands of Years Ago

Topic: Biology

Scientists found evidence that plague was killing people in ancient times, long before it became famous for causing the Black Death. They studied DNA from human remains at four burial sites in Siberia and discovered that nearly 40% of the people tested carried the plague bacterium.

Plague is often linked to rats and crowded cities. But new research shows that the disease was a threat thousands of years ago, even before farming and urban life became common. An international team of scientists studied ancient DNA from human remains at four burial sites in the Lake Baikal region of East Siberia. They found evidence of plague in 18 out of 46 people tested, which means nearly 40% carried the disease.

The researchers used a combination of genetic evidence, archaeology, and radiocarbon dating to understand what happened during these outbreaks. They found that many of the deaths occurred close together in time, and some graves contained siblings or parents and children who may have died during the same outbreak.

The ancient plague strains also contained a superantigen, a toxin-producing genetic factor not seen in historic plague strains. This finding changes our understanding of the earliest plague outbreaks: even before the bacterium evolved efficient flea-borne transmission, these ancient strains appear to have carried a potent combination of virulence factors that could make infection highly lethal.

Why It Matters

This discovery is important because it shows that plague was a deadly threat in ancient times. It also means that we need to rethink our understanding of how the disease spread and how it affected different communities.

Key Facts

• Plague was found in 18 out of 46 people tested at four burial sites in Siberia, which is nearly 40%.
• The ancient plague strains contained a superantigen, a toxin-producing genetic factor not seen in historic plague strains.
• Many of the deaths occurred close together in time, and some graves contained siblings or parents and children who may have died during the same outbreak.
• The researchers used a combination of genetic evidence, archaeology, and radiocarbon dating to understand what happened during these outbreaks.
• Plague was a threat thousands of years ago, even before farming and urban life became common.

Key Terms

Yersinia pestis

The bacterium that causes plague.

Superantigen

A toxin-producing genetic factor that can make an infection highly lethal.

Implications

This discovery is important because it shows that plague was a deadly threat in ancient times. It also means that we need to rethink our understanding of how the disease spread and how it affected different communities.