When we think of the plague, we associate it with medieval villages and doctors wearing haunting bird masks, but the world’s last major epidemic — the third pandemic — didn’t actually die down until the 1950s. The plague still exists, with a handful of infected people every year, but just like many other historically deadly diseases (scarlet fever comes to mind), we now know how to better treat it.

Last month, when a child in Idaho was diagnosed with the plague, it wasn’t a sign of the end as we know it, but rather a rare instance of a medieval disease surfacing once again. Unlike the Dark Ages, however, the Black Death is now treatable with a series of antibiotics.

In 2016, archaeologists in London used DNA evidence to isolate the cause of their last major outbreak, a pesky little bacterium called Yersinia pestis. Before we had the proper medication to treat it, this brutal contagion painfully swelled people’s lymph nodes to the point that blood gushed from their orifices.

black death plague
The uniform of a plague doctor during the Black Death pandemic. 

Rats were long known as the most common reservoirs for the plague, and droves of rodents in medieval streets were synonymous with this devastating period. We now know, however, that rats carried the disease but did not actually spread it. The likeliest vector is actually a flea that’s bitten an infected rodent who then transferred it to a human.

Since 1990 there have been two cases of the plague reported in Idaho and eight in Oregon. According to ABC News, in the US as a whole, around seven people are infected with the plague each year, all mostly concentrated in the rural West and Southwestern regions of the country.

While the plague is still a serious disease that should not be treated lightly, it’s rare, which means we’re better able to contain it: Experts work tirelessly to make sure they track down every single person the afflicted individual may have encountered.

So, if you are exposed to it, fret not. Modern medicine and a round of antibiotics will clear you up in no time.


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