By: Haley Bulluck-Munson

What is Smallpox?

An acute contagious viral disease, with fever and pustules usually leaving permanent scars. Smallpox is caused by a virus the variola virus. Smallpox gets its name from the puss-filled blisters that form during the illness. Smallpox is not related to chickenpox.

Smallpox Pictures

How is smallpox spread?

Smallpox is contagious. It spreads through tiny drops of an infected person's saliva when the person coughs, talks, or sneezes. Smallpox usually passes from person to person during close, face-to-face contact. It can also be spread from bed sheets and clothing.

How is it diagnosed?

Smallpox can be diagnosed by a patient's clinical signs and symptoms. When smallpox was common, an experiences clinician could make the diagnosis simply by looking at the rash and examing the patient. Any case that occurs now will likely be a result of bio terrorism or biological warfare.

Relative Frequency of Smallpox

There is no relative frequency of smallpox. The last case of smallpox in the United States was in 1949. The last case in the world was in Somalia in 1977. Vaccine campaigns have wiped out smallpox worldwide. Today, the smallpox virus is kept in two approved laboratories in USA and Russia.



Excessive bleeding


High fever

Raised pink rash


Disease Course

Once smallpox enters the body, there is a one to two week incubation period where the person has no sings of infection. Illness first becomes apparent with a sudden high fever of 101-105 F. Two to Fice days laster these flu-like symptoms go away. However, they are followed by the appearance of lesions in the mouth and by a rash on the skin that is most seen on the face and lower parts of the limbs.

Possible Complications

Most people do survive smallpox. People who recover from smallpox, usually have severe scares, especially on the face, arms, and legs. In some cases, smallpox may cause blindness.

Target Audience

Humans are the only natural hosts of Variola. Therefore, smallpox transmission does not occur through animals or insects.