Poliomyelitis (Polio, Infantile Paralysis)

What is polio?

Polio is a disease caused by poliovirus. The disease may affect the central nervous system. It can cause paralysis and even death. Widespread vaccination has helped eliminate wild poliovirus in the United States.

Who gets polio?

Anyone who is not up to date with their polio vaccines is at risk of getting polio.

Polio has been eliminated from most of the world, but the disease still occurs in other parts of the world. Travelers to these countries should be fully immunized. It only takes one person with polio traveling from another country to bring polio into the United States.

How is polio spread?

Poliovirus is very contagious. Poliovirus only infects people, entering the body through the mouth. It lives in an infected person's throat and intestines and spreads through person-to-person contact. It can also contaminate food and water in unsanitary conditions.

You can get polio from:

• Contact with the feces (poop) of an infected person
• Droplets from a sneeze or cough of an infected person (less common)

What are the symptoms of polio?

Most people who get infected with poliovirus will not have any visible symptoms. About 1 out of 4 people with poliovirus infection will have flu-like symptoms that can include sore throat, fever, tiredness, nausea, headache, and stomach pain. A smaller proportion of people will develop more serious symptoms such as meningitis (infection of the covering of the spinal cord), paralysis, or weakness in the arms, legs, or both.

Paralysis is the most severe symptom associated with poliovirus because it can lead to permanent disability and death. Between 2 to 10 out of 100 people who have paralysis from poliovirus infection die, because the virus affects the muscles that help them breathe.

How soon after exposure do symptoms appear?

The time from being exposed to getting sick can range from 3–35 days. For patients who develop paralysis, symptoms usually appear 7–14 days after exposure.

How is polio diagnosed?

Diagnostic testing can detect poliovirus in specimens from the throat, feces (stool), and occasionally cerebrospinal fluid. Testing works by isolating the virus in cell culture or by detecting the virus by polymerase chain reaction (PCR).

How long can an infected person carry polio?

An infected person can spread the virus to others immediately before and up to 2 weeks after symptoms appear. People who don't have symptoms can still pass the virus to others and make them sick.

What is the treatment for polio?

There is no cure for paralytic polio and no specific treatment.

Physical or occupational therapy can help with arm or leg weakness caused by polio. Therapy might also improve long-term outcomes, especially if implemented early in the course of illness.

Do people who have been in contact with someone with polio need to be tested and treated?

Contacts of individuals with polio should make sure they are up to date on the polio vaccine. Contacts who develop polio symptoms should be evaluated by a healthcare provider immediately and tested for polio.

How can polio be prevented?

Vaccination protects people against polio. The inactivated polio vaccine (IPV) is used currently in the United States. Children should receive four doses of IPV administered at 2 months, 4 months, 6–18 months, and 4–6 years. Adults who are known or suspected to be unvaccinated or incompletely vaccinated against polio should complete the IPV series. Adults who completed the series but who are at increased risk of exposure to poliovirus may receive one lifetime IPV booster. Contact your physician or local health department for further information about vaccination.

In addition to protecting yourself with the vaccine, practice good hand hygiene. Wash hands often with soap and water. Note that alcohol-based hand sanitizers do not kill poliovirus.

How can I learn more about polio?

• If you have concerns about polio, contact a healthcare provider.
• Contact your local health department. You can find your local health department at vdh.virginia.gov/health-department-locator/.
• Visit the CDC page on polio at cdc.gov/polio/about/ for more information.