Bubonic plague, the deadly scourge that wiped out half of Europe during the Middle Ages, still lurks in pockets of the globe, new research suggests.
Although plague is now rare in Europe, it recently sickened more than 10,000 people in Congo over a decade, and cases still occasionally emerge in the Western United States, according to a study published Sept. 16 in the American Journal of Tropical Medicine and Hygiene.
The plague bacteria, Yersinia pestis, had lain dormant in China’s Gobi Desert for centuries. But in the 1300s, it emerged with a vengeance, fanning out via trade routes from Asia to Europe and killing millions of people along the way. The plague was transmitted by fleas harbored by rats, which flourished in the overcrowded, filthy cities of the Middle Ages. By the end of the 1500s, between a third and half of Europe’s population had died from the Black Death. [Pictures of a Killer: Plague Gallery]
Even during the 1900s, the plague still killed millions of people, but since then, the advent of better hygiene in cities and swift treatment with antibiotics has reduced this erstwhile killer into a rare disease.