3D of single poliovirus particle

Polio, or poliomyelitis, is a disabling and life-threatening disease caused by poliovirus. The virus spreads from person to person and can invade an infected person’s spinal cord, causing paralysis (can’t move parts of the body). Most people who get infected with poliovirus will not have any visible symptoms or will have flu-like symptoms. A smaller proportion of people with poliovirus infection will develop other, more serious symptoms that affect the spinal cord and could lead to paralysis. There is no cure, but there are safe and effective vaccines to prevent polio.


Key Facts

  • Polio was eliminated (meaning no ongoing spread of the disease for more than 12 months) in the United States in 1979. We continue to vaccinate our nation’s children knowing that the disease still occurs in other parts of the world and could easily be brought into the U.S.
  • Most people infected with poliovirus have no symptoms. About 24% have minor flu-like symptoms that don’t last long. They may have a sore throat, fever, tiredness, nausea, headache, or stomach pain. A small proportion of people who get poliovirus will develop meningitis (infection of the covering of the spinal cord and/or brain) or paralysis in the arms and/or legs.
  • While borders can’t stop diseases from spreading, vaccines can. Fortunately, we have a good level of protection against polio in the United States. Most of us have been vaccinated, and current polio vaccination coverage among young children in the United States is 93%.


Young girl pulling suitcase through airport
Polio and Travel

Polio still exists in a few countries in Africa and Asia. Even if you were previously vaccinated, you may need a one-time booster shot before you travel anywhere that could put you at risk for getting polio. See your healthcare provider for more information.

Young girl with polio
Widespread Panic

In the late 1940s to the early 1950s, polio outbreaks in the United States increased in frequency and size. Polio crippled an average of more than 35,000 people in the U.S. each year. Parents were frightened to let their children go outside, especially in the summer when the virus seemed to peak.

Doctor examining child on mother's lap and smiling
Vaccination Schedule

For best protection, children should get four doses of polio vaccine. This vaccine is given as a shot in the arm or leg and is extremely safe. Ideally, your child should receive a dose at ages 2 months, 4 months, 6 through 18 months, and then a booster dose at age 4 through 6 years.

Prevention Tips

  • Polio vaccine provides the best protection against polio.
  • Children should get four doses of inactivated polio vaccine (IPV) to protect against polio, with one dose at each of the following ages:
    • 2 months
    • 4 months
    • 6 through 18 months
    • 4 through 6 years
  • Children who will be traveling to a country where the risk of getting polio is greater should complete the vaccination series before leaving for their trip. If a child cannot complete the routine series above before leaving, an accelerated schedule is recommended as follows:
    • first dose at age 6 weeks or older,
    • a second dose 4 or more weeks after the first dose,
    • a third dose 4 or more weeks after the second dose,
    • a fourth dose 6 or more months after the third dose.
  • Most adults do not need polio vaccine because they were already vaccinated as children. But three groups of adults are at higher risk and should consider polio vaccination in the following situations:
    • You are traveling to a country where the risk of getting polio is greater. Ask your healthcare provider for up-to-date information on whether you need to be vaccinated.
    • You are working in a laboratory and handling specimens that might contain polioviruses.
    • You are a healthcare worker treating patients who could have polio or have close contact with a person who could be infected with poliovirus.
  • Adults in these three groups who have never been vaccinated against polio should get three doses of IPV:
    • The first dose at any time,
    • The second dose 1 to 2 months later,
    • The third dose 6 to 12 months after the second.
Page last reviewed: January 17, 2020