What is polio?
Polio, or poliomyelitis, is a disease that spreads from person to person. It is caused by the poliovirus. The virus attacks the nervous system. In serious cases, it can cause paralysis (where you can't move parts of the body). The paralysis may be lifelong and can sometimes be life-threatening.
Because of vaccines, polio is rare in the United States. But polio does occur in some parts of the world, and travelers can spread the virus.
How does polio spread?
The poliovirus is very contagious. It spreads through contact with:
- The stool (poop) of person who has the infection
- Droplets from a sneeze or cough of someone who has the infection
This contact can happen if:
- You get contaminated stool or droplets on your hands and then touch your mouth
- A child puts contaminated toys or other objects into their mouth
- You share food or utensils with someone who has the infection
People who have the infection can spread it to others just before and up to several weeks after the symptoms appear. People who don't have symptoms can still spread the virus to others and make them sick.
Who is more likely to develop polio?
Polio mainly affects children under age 5. But people of any age (including adults) who are unvaccinated are at risk of developing polio. People who live in or travel to areas where there is polio are more likely to get polio.
What are the symptoms of polio?
Most people who get infected with poliovirus do not have any symptoms. But one out of four people who get polio will have flu-like symptoms. These symptoms usually last 2 to 5 days, and they include:
In rare cases, polio can be very serious. It can lead to:
- Meningitis, an infection of the covering of your spinal cord and/or brain.
- Weakness or paralysis in your arms, legs, or both. This paralysis or weakness can last a lifetime. It is possible for the paralysis to become life-threatening if it affects the muscles that you use to breathe.
- Post-polio syndrome (PPS), which happens later in life.
What is post-polio syndrome (PPS)?
Post-polio syndrome (PPS) is a condition that affects polio survivors many years after they recovered from polio. It usually happens 15-40 years later. It is not contagious.
People who get PPS start having new weakening in muscles that were previously affected by the polio infection. Symptoms may range from mild to serious. The symptoms of PPS include:
- Muscle weakness
- Muscle atrophy (wasting away of muscles)
- Loss of muscle function
- Mental and physical fatigue
- Joint pain
- Curving of the spine (scoliosis)
PPS is rarely life-threatening, but the symptoms can interfere with your daily life.
How is polio diagnosed?
If you think you or someone in your family has symptoms of polio, call your healthcare provider right away or go to an emergency room.
To find out if you or your child has polio, the provider:
- Will do a physical exam.
- Will take a detailed medical history, including your vaccination history and history of any recent travel.
- Will collect samples of body fluids, such as stool, saliva, blood, urine, and spinal fluid. Poliovirus is most likely to be detected in stool specimens.
- May do an MRI to look at pictures of the spinal cord.
What are the treatments for polio and post-polio syndrome (PPS)?
There is no cure or specific treatment for polio. For a mild case, getting rest and drinking plenty of liquids may help with some of the symptoms.
If the polio is more serious, you or your child may need:
- Physical or occupational therapy to help with arm or leg weakness. The earlier therapy is started, the better.
- Pain relievers to help with pain and treat fever. If your child is sick, do not give them aspirin unless their provider tells you to.
- A ventilator to help with breathing if the breathing muscles are weak or paralyzed.
There is no cure for PPS. Treatments may help you manage your symptoms. They include:
- Non-fatiguing exercises (exercises that do not cause pain or fatigue that lasts more than 10 minutes). These exercises may improve muscle strength and reduce tiredness. Your provider can help you figure out which exercises are best for you.
- Mobility aids.
- Ventilation equipment.
- Lifestyle changes, such as eating a healthy diet, getting enough sleep, and not smoking.
Can polio be prevented?
There are two types of vaccine that can prevent polio:
- Inactivated poliovirus vaccine (IPV) given as an injection in the leg or arm, depending on how old you are. Since 2000, this has been the only polio vaccine used in the United States.
- Oral poliovirus vaccine (OPV) is given as drops in the mouth. It is still used throughout much of the world.
Children in the United States get four doses of PV as part of their routine childhood immunizations. Most adults in the United States were vaccinated against polio as children.
There is a one-time IPV booster. It may be given to adults who have completed their polio vaccinations but are at higher risk of contact with poliovirus. You may be at higher risk if you are:
- Traveling to a country where the risk of getting polio is greater
- Working in a laboratory or healthcare setting and handling samples that might contain polioviruses
- A healthcare worker who has contact with patients who could have polio
Another way to help prevent the spread of polio is to wash your hands often with soap and water. Alcohol-based hand sanitizers will not kill poliovirus.
Centers for Disease Control and Prevention
- Polio (Mayo Foundation for Medical Education and Research) Also in Spanish
- Polio Vaccination (Centers for Disease Control and Prevention)
- Post-Polio Syndrome (National Institute of Neurological Disorders and Stroke) - Short Summary
- Post-Polio Syndrome (National Institute of Neurological Disorders and Stroke) Also in Spanish
- Travelers' Health: Poliomyelitis (Centers for Disease Control and Prevention)
- Polio Photos (Centers for Disease Control and Prevention)
Journal Articles References and abstracts from MEDLINE/PubMed (National Library of Medicine)
- Article: Evaluation of acute flaccid paralysis surveillance system in the River Nile...
- Article: Vaccination against poliomyelitis in Brazil from 2011 to 2021: successes, setbacks,...
- Article: Mobile Money and the importance of timely, complete payments to frontline...
- Polio and Post-Polio Syndrome -- see more articles
Find an Expert
- National Institute of Allergy and Infectious Diseases
- National Institute of Neurological Disorders and Stroke Also in Spanish
- Post-Polio Directory: Post-Polio Clinics, Health Professionals, Support Groups (Post-Polio Health International including International Ventilator Users Network)
- World Health Organization