Hendrik Poinar’s latest work that looks into the Bubonic plague, which was caused by the rodent-borne bacterium Yersinia pestis, is featured in the New York Times and more than 250 other notable publications, and counting. To view updated coverage follow us on Twitter.
Bubonic plague, caused by the rodent-borne bacterium Yersinia pestis, has killed a large fraction of the earth’s population at least twice — most famously in the medieval Black Death, but before that in the Plague of Justinian, which began in A.D. 541. That pandemic, named for the Byzantine emperor, may have killed half of Europe and Asia; it hastened the collapse of the Roman Empire’s remnants and ushered in the Dark Ages.
Plague is no longer a leading killer, but it is still with us. There are 155 known strains in circulation, said Hendrik N. Poinar, an evolutionary geneticist at McMaster University in Ontario. A recent outbreak in Madagascar killed 20 residents of one village in a week.
In a study published Monday by Lancet Infectious Diseases, Dr. Poinar and colleagues describe rebuilding the genome of the Justinian strain from fragments found in teeth from bodies in a sixth-century graveyard in what is now Bavaria. That strain apparently died out, he said, while all modern ones are descended from the Black Death strain.
The plague genome goes through “rapid-fire boom and bust” mutation cycles, he said. It “sits quietly in rodents” between sudden widespread animal outbreaks, during which it may change 10 percent of its genes.
Although most modern human cases can be cured with antibiotics and the Black Death strain has been shown to be susceptible to tetracycline, new antibiotic-resistant strains have emerged recently.
“I wouldn’t turn a blind eye to it,” Dr. Poinar said.