What is The Plague?

You may think that the plague, once called the Black Death, must be extinct, disappearing with knights in armor and village blacksmiths. But the disease that swept the world hundreds of years ago still lives. And it’s still dangerous.

But unlike our ancestors, we know what causes the plague. And with quick treatment, it can be cured.

Plague Basics

The plague is caused by bacteria called Yersinia pestis. It’s usually spread by fleas. These bugs pick up the germs when they bite infected animals like rats, mice, or squirrels. Then they pass it to the next animal or person they bite. You can also catch the plague directly from infected animals or people.

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Thanks to treatment and prevention, the plague is rare now. Only a few thousand people around the world get it each year. Most of the cases are in Africa (especially the Democratic Republic of Congo and Madagascar), India, and Peru.

The U.S. sees about seven cases a year, mostly in rural or remote areas in Southwestern states like Arizona, Colorado, New Mexico, and California.


After people catch the plague, the symptoms start 1-6 days later. You feel very sick and weak and may have a fever, chills, and headaches. Other symptoms depend on the three main kinds of plague:

Bubonic plague. This is the most common type. It causes buboes, which are very swollen and painful lymph nodes under the arms, in the neck, or in the groin. Without treatment, the bacteria can spread to other parts of the body.

Septicemic plague. This type is more dangerous than bubonic plague. It’s when the bacteria have moved into the blood. Signs include:

  • Bleeding under the skin or from the mouth, nose, or bottom
  • Blackened skin, especially on the nose, fingers, and toes
  • Belly pain, diarrhea, vomiting, and shock

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Pneumonic plague. This is when the bacteria are in the lungs. It’s the rarest form of the disease. It’s deadly without treatment. It’s also very contagious because the plague can spread through the air when a person coughs. Symptoms include:

  • Cough, sometimes with blood
  • Trouble breathing
  • Nausea and vomiting

Who Gets It?

For most people, the chances of the plague are low. But you’re more likely to get if you visit or live in an area with the plague and you:

  • Touch a living or dead animal that might have been infected, like a rat, mouse, squirrel, rabbit, or chipmunk
  • Work with animals regularly
  • Spend a lot of time outdoors working, hiking, camping, or hunting
  • Spend time with someone who has the plague


If you’ve been in an area with the plague and have symptoms, see a doctor right away. Hours can make a difference. Your doctor can run tests of blood, spit, or fluid from your lymph nodes to check for plague germs.

If you’ve been around someone who has the plague, your doctor may start treatment even if you don’t have symptoms. If you must be near the person, wear tight-fitting disposable surgical masks so you won’t breathe in the plague bacteria.

If you have the plague, you'll be admitted to the hospital. You'll get antibiotics like:

  • Ciprofloxacin (Cipro)
  • Doxycycline (Vibramycin)
  • Gentamicin (Garamycin)
  • Levofloxacin (Levaquin)

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Treatment works well. With antibiotics, most people get better within a week or two. But without treatment, most people with the plague die.


There’s no vaccine for the plague in the U.S. So if you have a chance of contact with plague germs, take steps to protect yourself.

If you travel to Africa, Asia, or South America, check for traveler notices about plague outbreaks on the CDC website. Avoid areas with the plague if you can, and stay away from sick or dead animals while you’re there.

If you live in an area where there’s been a case of the plague:

  • Fill holes and gaps in your home to stop mice, rats, and squirrels from getting in.
  • Clean up your yard. Get rid of piles of leaves, wood, and rocks where animals might make their homes.
  • Use bug repellent with DEET to prevent flea bites when you hike or camp.
  • Wear gloves if you have to touch wild animals, alive or dead.
  • Use flea control sprays or other treatments on your pets.
  • Don’t let outdoor pets like cats or dogs sleep in your bed.

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