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What Is Smallpox?

What Is Smallpox?

Smallpox is a very serious illness caused by a virus called the variola (say: vair-ee-OH-luh) virus. Smallpox gets its name from the pus-filled blisters (or pocks) that form during the illness. Although the names may sound alike, smallpox is not related to chickenpox, which is a milder disease caused by a different virus.

You may have heard about smallpox and wondered what it is or whether you or anyone you know could get it. Some people are worried that the germ that causes smallpox could be spread and used as a weapon. This would be difficult for anyone to do. Right now, there are no cases of smallpox disease in the United States. In fact, the last case of smallpox in the United States was in 1949, and the last case in the world was in 1977.

How Is Smallpox Spread?

Smallpox is contagious. That means the virus can spread to others. It spreads through tiny drops of an infected person's saliva (spit) when the person coughs, talks, or sneezes. Smallpox usually passes from person to person during close, face-to-face contact.

What Is the Smallpox Vaccine?

A vaccine (say: vak-SEEN), a type of shot, can prevent infection with the virus that causes smallpox. Years ago, people were vaccinated against smallpox. Today, smallpox vaccines aren't given because nobody has had the disease for many years. Although you can't — and don't need to — get a smallpox vaccine right now, there is a supply of the vaccine in case there's an outbreak of the disease. Scientists also are working to make more vaccine to have on hand for the future.

What Are the Signs of a Smallpox Outbreak?

If someone does get smallpox, a doctor can recognize the disease because it causes a special kind of rash. The rash shows up as blisters on the skin that fill with fluid and crust over. This might sound like chickenpox, but the blisters look different from the blisters that chickenpox causes. The other symptoms of smallpox are like those of many other less serious illnesses: fever, headache, backache, and feeling tired.

How Is Smallpox Treated?

There are no pills that can treat smallpox, but scientists are doing research to try to develop medicine for the disease. If someone does become infected with the smallpox virus, getting the vaccine within a few days of becoming infected can lessen the disease's symptoms.

If you feel scared when you hear about smallpox, remember that it's very unlikely that you, your family, or anyone you know will ever come in contact with the virus that causes it. Talking to your teacher or parent may make you feel better and give you answers to any other questions you may have.

Reviewed by: Steven Dowshen, MD
Date reviewed: November 2017

Note: All information on KidsHealth® is for educational purposes only. For specific medical advice, diagnoses, and treatment, consult your doctor.

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