Plague is an illness you get from Yersinia pestis bacterium. You usually get the most common form (bubonic plague) from flea bites, but you can get pneumonic plague from someone who’s infected. Plague caused deadly pandemics in the past and still exists in many countries today. You can survive plague if you’re treated with antibiotics quickly.
Plague is an illness you get from the bacterium Yersinia pestis (Y. pestis). Plague is a zoonotic disease, which means you can get it from animals and they can get it from you. This disease usually spreads through bites from fleas that previously bit an infected animal.
There are three types of plague. Which type you have depends on where in your body Y. pestis ends up. Bubonic plague infects your lymph nodes, septicemic plague is in your blood and pneumonic plague affects your lungs.
Today we still use the word “plague” to mean illness caused by Yersinia pestis. Usually, we also call it by the specific type of plague it is — bubonic, septicemic or pneumonic.
Yes, plague still exists. It’s most common in parts of Africa, but a few cases are reported in Asia, South America and the U.S. every year.
The three types of plague — bubonic, septicemic and pneumonic — are each named for the part of your body that gets infected by Y. pestis.
Bubonic plague is the most common form of plague. It’s also the most survivable. With quick antibiotic treatment, you have about a 95% chance of recovering from bubonic plague.
Bubonic plague makes one or more lymph nodes painful and swollen. The affected lymph nodes are usually near where an infected flea bit you.
When Y. pestis gets into your blood, you have septicemic plague. It destroys your tissues, leading to gangrene and organ failure. You can get septicemic plague from:
You get pneumonic plague when Y. pestis bacteria gets into your lungs. It’s the least common and most dangerous type of plague.
Pneumonic plague can spread from person to person through coughing and sneezing, just like the common cold. You can also get it from close contact with infected animals or from bacteria moving to your lungs from another part of your body (secondary infection).
Pneumonic plague causes severe pneumonia and respiratory failure. If not treated, most people with pneumonic plague die within days.
Bubonic plague and pneumonic plague are caused by the same bacterium, Y. pestis. Bubonic plague is a bacterial infection in your lymph nodes and pneumonic plague is a bacterial infection in your lungs.
Plague mostly affects people living in a few countries in Africa, but cases are also reported in the Americas and Asia every year. It’s most common in Madagascar and the Democratic Republic of Congo.
In the U.S., you’re more likely to get plague in rural areas of western states. You’re at higher risk if you work with animals in an area where plague is found.
While it still exists, plague is extremely rare now. Worldwide, 1,000 to 2,000 people are diagnosed with plague every year. Only about seven cases are reported in the U.S. each year.
When Y. pestis enters your body, it hides from your immune system, allowing it to multiply and spread out. When it gets into cells, it releases a toxin to kill the cell.
Y. pestis can infect your lymph nodes (bubonic plague), causing large swellings called buboes. If it gets in your blood (septicemic plague), it can damage your organs. If it gets into your lungs (pneumonic plague), it can cause severe inflammation and respiratory failure.
The deadliest plague killed millions of people in Europe, Asia and North Africa in the mid-1300’s. Hunger and poor sanitation made people vulnerable to sickness, and it spread to different countries through trade routes.
It’s usually what people mean when they talk about “the plague.” This plague also is sometimes referred to as the "Black Death."
Some symptoms of plague happen in all types and some depend on whether you have bubonic, septicemic or pneumonic plague.
Symptoms of plague include:
Plague looks different depending on which part of your body is infected. Septicemic plague can cause gangrene, which destroys your tissues. Your fingers, hands, toes, feet or other body parts might turn black.
If you have bubonic plague, you’ll have one or a few very large, noticeable lymph nodes. Many people use medieval artwork to show bubonic plague, but the people in the artwork are usually shown with sores all over. This isn’t what plague looks like. (The iconic artwork likely shows smallpox or leprosy.)
The bacterium Yersinia pestis (Y. pestis) causes plague. Rats and other animals carry Y. pestis, but humans usually get infected by being bitten by fleas or lice carrying the bacteria. Y. pestis gets into your lymph nodes, bloodstream or lungs and makes you sick.
Y. pestis, the bacterium that causes plague, can spread to people from animals or other people. You can get plague:
Animals can also get plague from other animals.
Most people think of rats as the only carriers of plague, but many animals carry and spread the disease. Which animals are more likely to have plague is different depending on where you live. Research shows plague can affect:
Bubonic and septicemic plague are not contagious, but pneumonic plague is. Pneumonic plague can spread from person to person through coughing, sneezing and close contact.
No, plague isn’t a virus. Plague happens because of the bacterium Yersinia pestis.
The most common sign of bubonic plague is a swollen and painful lymph gland called a bubo. Your provider may suspect plague if you have a flea bite or a bubo.
Make sure you mention to your provider if you:
To diagnose plague, your healthcare provider will take a sample of your blood, your spit (mucus or phlegm) or fluid from a lymph node. They’ll send your sample to a lab to look for signs of Y. pestis bacterium.
Plague needs to be treated with antibiotics right away. Your healthcare provider will give medication to you either through your veins (IV) or in a pill to take. Depending on your symptoms and risk, you may start antibiotics even before your provider has your test results.
You take antibiotics by mouth or through your veins to treat plague. Your healthcare provider might prescribe one or more of these antibiotics:
You can reduce your risk of plague by avoiding flea bites and being careful around animals that could be infected.
Vaccines aren’t widely used to protect against plague. Scientists are currently working on creating more effective plague vaccines.
You need to get treated immediately if you have plague. While antibiotics work well, you have the best chance of getting better if you start taking them within 24 hours of noticing symptoms. You may be given extra oxygen or other treatments to manage your symptoms.
If treated, you’ll probably feel better in a week or two. Buboes from bubonic plague might take a few weeks to go away.
Many complications of plague happen quickly and are life-threatening, including:
Immediate treatment with antibiotics will help you survive the plague. With quick treatment, about 90% of people with all forms of plague survive.
Without treatment, plague is nearly always fatal. With treatment, there’s a 5 to 15% mortality (death) rate for bubonic plague and around a 50% mortality rate for pneumonic and septicemic plague.
Contact your healthcare provider for immediate medical attention if you:
There were three infamous plague pandemics in history:
A note from Cleveland Clinic
Millions of people died in plague pandemics in the past. It still exists today, but thanks to modern sanitation and antibiotics, very few people die from it — though it’s critical that you receive treatment immediately. If someone tells you they’re “avoiding it like the plague,” feel free to congratulate them on their safe animal handling and flea management strategies.
Last reviewed by a Cleveland Clinic medical professional on 08/22/2022.
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