Amber-Encased Flea Could Carry Ancient Plague Strain

The baffling discovery of a 20-million year old amber-encased flea carrying bacteria thought to be the ancestor of the plague bacteria could change a piece of history.

The 20-million year old flea revealed traces of bacteria that are similar in shape and size with Yersinia pestis. Yersinia pestis is the bacteria that led to mass deaths during the medieval ages, both in Europe and across the world. The bubonic plague or the Black Death is nothing short of a horror story, ripe with deaths counted anywhere between 30 million and 200 million people.

And yet, the plague and strains of Yersinia pestis did not disappear with the passing of medieval times. Even today, Yersinia pestis resides in rodents and other animals and is easily transmitted to pests such as fleas which are feeding on them. From here to passing the strain to humans, there’s only one small bite.

But if the plague has survived into modernity, what is to say that it couldn’t have been on Earth long before the medieval age when it claimed most of deaths?

This amber-encased flea could pinpoint the answer. The scourge that killed millions during the 14th century could have older roots than that, possibly even predating the human race.

Entomologist George Poinar, Jr. with the College of Science at Oregon State University, lead author on the study describing the findings in the 20-million year old amber fossil stated:

“Aside from physical characteristics of the fossil bacteria that are similar to plague bacteria, their location in the rectum of the flea is known to occur in modern plague bacteria. And in this fossil, the presence of similar bacteria in a dried droplet on the proboscis of the flea is consistent with the method of transmission of plague bacteria by modern fleas”.  

The findings, published in the Journal of Medical Entomology, indicate that for the time being, it can’t be stated with certainty that the bacteria found in the amber-encased flea’s proboscis and rectum is indeed an ancient strain of the Yersinia pestis. However, given that they are a coccobacillus bacteria, as well present almost spherical and rod shape, all clues point in this direction.

The amber-encased flea was found in an amber mine located between Santiago and Puerto Plata, Dominican Republic. At the time when the flea was trapped in the semi-precious stone, the geographic area would have been a tropical forest with high humidity. Setting aside the fact that the fossil in itself is a rare-treat, the bacteria it carries is an even more surprising finding.

This alleged ancient strain of the Yersinia pestis could rewrite history. According to modern genomic studies, the cycle flea-plague-vertebrate only dates back to 20,000 years. This finding could prove that it exists for over 20 million years.

Photo Credits: Phys.org