Bubonic plague discovered in ancient Egyptian mummy DNA

Although the bubonic plague is most often associated with its deadly impact on 14th century Europe, traces of Yersinia pestis have also been found in skeletons found in modern-day Russia dating as far back as 5,000 years ago. Thanks to recent analysis, however, researchers believe they have confirmed the first known plague case outside Eurasia: a 3,290-year-old, ancient Egyptian mummy.

Y. pestis, also known as the Black Death, is one of history’s most notorious diseases. Usually transmitted by fleas hitching a ride on rodents, the bubonic plague attacks the lymphatic system, and initially results in flu-like symptoms a few days after infection. From there, things often get far more grim—and fatal. Lymph nodes in the groin, underarm, and neck begin to painfully swell while the infected victim develops a high-grade fever, chills, and even seizures. Hematemesis (vomiting blood) sets in, along with the swollen lymph nodes developing into buboes that often rupture. Internal hemorrhaging causes large portions to bruise and turn necrotic—symptoms that earned the plague its “Black Death” moniker. Without proper modern antibiotic treatments, 30-90 percent of patients can ultimately die as a result of the disease.

Apart from its spread through Europe between 1346 and 1353, the bubonic plague is believed to be the root cause of the Eastern Roman Empire’s Plague of Justinian in the 6th century CE, as well as a third epidemic that occurred across China, Mongolia, and India in 1855. But as researchers explained during a presentation at the European Meeting of the Paleopathology Association, Y. pestis is confirmed to have existed at least at one point in ancient Egypt, as well.

The team reached their conclusion after examining a mummy housed in Italy’s Museo Egizio that dates back to the Second Intermediate Period or early New Kingdom. According to researchers, DNA extracted from both intestinal contents and bone tissue contained traces of Y. pestis, implying the victim endured an advanced stage of the plague before dying.

“This is the first reported prehistoric Y. pestis genome outside Eurasia, providing molecular evidence for the presence of plague in ancient Egypt,” the team wrote in their presentation abstract.

Experts have theorized about the bubonic plague’s presence in ancient Egypt for decades. As IFL Science notes, a research team in 2004 found millennia-old fleas at an archeological site in Amarna on the banks of the Nile River. This, coupled with a 3,500-year-old Egyptian medical text known describing “a bubo [whose] pus has petrified,” led scientists to believe the Black Death arrived in communities along the riverbanks thousands of years ago. But without any direct evidence of Y. pestis, the theory remained unproven. The discovery of bubonic plague remnants in mummy DNA, however, appears to finally provide proof of its existence in ancient Egypt.

The team can’t be sure how widespread Y. pestis was in the region just yet, but they hope their findings will help others “study virulence-associated genes, and to characterize its possible modes of transmission and pathology.”