Smallpox is an illness caused by the variola virus. The main sign of smallpox is a rash that starts as flat red spots that turn into blisters. Other symptoms include fever, headache, fatigue, and vomiting. Smallpox is spread from person to person through infected droplets.

It is important to know that the last naturally occurring case of smallpox in the world happened in 1977. The World Health Assembly said the disease was completely eradicated in 1980.

Path to safety

The smallpox vaccine was created to protect against infection. It helps our bodies develop immunity to the smallpox virus. Unlike most vaccines, this vaccine doesn’t contain a weakened or killed form of variola virus. It cannot cause smallpox. However, it has been known to cause reactions in certain groups of people, such as:

  • Children younger than 12 months of age.
  • Women who are pregnant or nursing.
  • People who have eczema or another chronic skin condition.
  • People who have a condition or get treatment that weakens their immune system.
  • People who live or work with someone who has a skin condition or weakened immune system.
  • People who are allergic to any ingredient in the smallpox vaccine.
  • People who have a heart condition.
  • People who have 3 or more of the following risk factors:
    • High blood cholesterol.
    • High blood pressure.
    • Diabetes or high blood sugar.
    • Smoking.
    • Family history of heart disease.

Things to consider

The smallpox vaccine is no longer available to the public. In 1972, routine smallpox vaccination in the United States ended. In 1980, the World Health Organization (WHO) declared smallpox was eliminated. Because of this, the public doesn’t need protection from the disease.

Today, the smallpox virus only exists in samples in research laboratories. The vaccine still is used to protect certain people, like those who work with the virus. The United States also has a supply of smallpox vaccine available in case of an outbreak, which is unlikely. If you got vaccinated before 1972, you are no longer protected. Studies show that the vaccine is effective for 3 to 5 years.

Questions to ask your doctor

  • How do I know if I should get the smallpox vaccine?
  • Does smallpox still exist in third-world countries?


Centers for Disease Control and Prevention: Smallpox Vaccine