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What is smallpox?

Smallpox is a disease that is caused by a virus. The last known case of smallpox was in 1977. Routine vaccinations were stopped in 1972.

How do you get smallpox?

The smallpox virus is passed through the air when an infected person coughs or sneezes. It can also be spread through direct contact.

What are the symptoms of smallpox?

  • Fever
  • Severe tiredness
  • Headache and backache
  • Red, flat rash
  • Blisters
  • Abdominal pain
  • Vomiting and diarrhea

How is smallpox diagnosed?

Your healthcare provider may be able to diagnose smallpox based on your symptoms and physical exam. He may also take a tissue sample from your rash and send it to a lab for tests.

How is smallpox treated?

There is no medicine that will get rid of the smallpox infection. Your healthcare provider will treat your symptoms. You may be given IV liquids to help prevent dehydration. You may need medicine to decrease pain and lower your fever. You may also need antibiotics if you develop a bacterial infection. You can get the smallpox vaccine up to 4 days after you are exposed to the virus. This may prevent a severe infection.

What are the risks of smallpox?

You may get a skin infection from the blisters. You may develop a lung, eye, or brain infection. Scar tissue near your eyes may cause blindness. You may develop an infection or arthritis in your joints. You may have deep scars on your skin. These problems can be life-threatening.

What should I do if I am exposed to smallpox?

Exposure to smallpox is considered a medical emergency. Call your healthcare provider immediately if you think you have been exposed. You may be isolated in the hospital. You may receive the smallpox vaccine. Anyone who has been in direct contact with you may need the vaccine. Your healthcare provider will call your local health agency to notify them of your infection.

Where can I find more information about smallpox?

  • Centers for Disease Control and Prevention
    1600 Clifton Road
    Atlanta , GA 30333
    Phone: 1- 800 - 232-4636
    Web Address:

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Further information

Always consult your healthcare provider to ensure the information displayed on this page applies to your personal circumstances.

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Mayo Clinic Reference