Oregon just had their first case of bubonic plague in years—yes, the same bubonic plague responsible for the historical Black Death pandemics. But don’t panic just yet. Plague is more common than you might think, and more treatable, too. 

There are a few bubonic plague cases every year, actually

From the headlines, you might think this is the first case of plague in the U.S. in eight years, or the first in the world in eight years. It’s actually just the first case Oregon has had since 2015. There have been cases in other states and elsewhere in the world. Plague isn’t absent from the modern world, it’s just rare.

According to the CDC, the U.S. had nine cases (with two deaths) in 2020, the most recent year on their plague stats page. There was only one case in each of 2018 and 2019, but five cases in 2017, and a whopping 16 in 2015. That 2015 mini-outbreak is the last time there was a plague case in Oregon specifically. 

Why this steady trickle of cases? Because a low level of plague is always simmering in rodent populations, especially in the southwest. (Researchers believe that plague originally came from rodents, possibly marmots in central Asia; it later spread to rats, and in the U.S. it now circulates in prairie dogs.) 

This is why it’s good to stay away from sick or dead rodents. In the recent Oregon case, the person seems to have caught plague from their cat. We don’t know for sure where the cat got it from, but one strong possibility is that the cat got it from a local wild rodent (or its fleas).

Antibiotics work against bubonic plague

Plague sounds scary because we’ve heard the stories about the plague pandemics in medieval Europe. And, sure, if you lived in medieval Europe and caught the plague, you would be kind of screwed. 

But plague is caused by a bacterium, Yersinia pestis. That bacterium can be killed with modern antibiotics. It’s important to get treatment promptly, since this disease can still be fatal, and the earlier you’re treated the better. 

The CDC recommends seeking medical care as soon as you suspect you may have plague. Tell your doctor if you have recently been to (or live in) the western United States. One of the characteristic symptoms of plague is an extremely swollen and painful lymph node, called a bubo. Your doctor can test your blood or the bubo for signs of plague, and treat you accordingly. 

How to protect yourself from the plague 

The CDC has a list of tips for plague prevention here. Remember, this is an uncommon disease, so plague is not likely to be coming for you personally. But here are some sensible precautions: 

  • Keep rodents away from your home (for example, by removing brush piles and food sources near the house).

  • Use insect repellents on yourself and your pets to reduce your chances of getting flea bites.

  • If your dog or cat roams free in plague-endemic areas, don’t let them sleep on your bed. 

Where are those plague-endemic areas? The CDC says most plague cases come from northern Arizona, northern New Mexico, southern Colorado, southern Oregon, California, and western Nevada.