Yes, it’s rare. No, it’s not gone. Here’s what to know.
When most people hear “plague,” they picture medieval Europe—not modern-day America. But plague in the U.S. is real, even if it’s rare.
Each year, a handful of people are infected with Yersinia pestis, the bacterium that causes plague. In most cases, early treatment with antibiotics is highly effective. But knowing where and why it still happens can help you stay safe—especially if you live in or travel to certain parts of the country.
The Hot Spots: Where Plague Still Appears
According to the Centers for Disease Control and Prevention (CDC), plague cases in the U.S. are almost entirely confined to the rural West, particularly:
- Northern Arizona
- New Mexico
- Colorado
- California
- Southern Oregon
- Parts of Utah and Nevada
These regions are home to the natural reservoirs of the disease—mainly wild rodents like prairie dogs, squirrels, and chipmunks. The fleas that live on these animals can carry the plague bacteria and pass it to pets or people.
Why It Lingers in These Areas
Plague survives in what scientists call an enzootic cycle—meaning it circulates in small wild animals and their fleas without causing major outbreaks. Every so often, the bacteria jump to a human through:
- The bite of an infected flea
- Contact with a sick or dead animal
- In rare cases, inhaling airborne droplets from an infected person or animal (as in pneumonic plague)
Warmer temperatures and increased rodent activity in spring and summer often lead to seasonal flare-ups. A sudden die-off of prairie dogs or ground squirrels in an area can be a warning sign that plague is present in the environment.
Who Is Most at Risk?
You’re more likely to encounter plague if you:
- Live in or visit rural areas in the western U.S.
- Hike, camp, or spend time outdoors where rodents are active
- Let your pets roam or hunt in nature
- Handle sick or dead animals
While anyone can get plague, it’s most common in children under 15 and adults over 60, particularly those with regular exposure to the outdoors or wildlife.
📌 How to Reduce Your Risk
The risk of catching plague is low—but it’s not zero. Here’s how to stay safe:
- Avoid touching wild rodents or dead animals.
- Keep pets flea-free with veterinarian-approved treatments.
- Don’t let pets roam freely in known plague zones.
- If you see an area with sudden rodent die-offs, report it to local health officials.
- Use insect repellent and wear long sleeves and pants when outdoors in high-risk areas.
The Bottom Line
Plague may sound like a thing of the past, but it hasn’t disappeared. Knowing where it exists—and how it spreads—can help you and your family enjoy the outdoors without worry. In the rare event that you do get sick, early diagnosis and treatment are life-saving.
