Polio, or poliomyelitis, is a disabling and life-threatening disease caused by the poliovirus. The virus spreads from person to person and can infect a person’s spinal cord, causing paralysis.
How does polio spread?
Poliovirus is very contagious and spreads through person-to-person contact.
- It lives in an infected person’s throat and intestines.
- It can contaminate food and water in unsanitary conditions.
Poliovirus only infects people. It enters the body through the mouth. It spreads through:
- Contact with the feces (poop) of an infected person
- Droplets from a sneeze or cough of an infected person (less common)
You can get infected with poliovirus if:
- You have picked up minute pieces of feces on your hands and touched your mouth.
- You put objects contaminated with feces, such as toys, in your mouth.
How common is polio?
Symptomatic polio is rare in many parts of the world, thanks to vaccination programs. Most countries consider polio eliminated, but when people stop vaccinating, polio can start spreading again.
Who is at risk for polio?
You’re most at risk for polio if you aren’t vaccinated and you:
- Live in or travel to an area where polio hasn’t been eliminated.
- Live in or travel to an area with poor sanitation.
- Are under 5.
- Are pregnant.
Prevention and Treatment
There are two types of vaccines that can prevent polio:
- Inactivated poliovirus vaccine (IPV) is an injection in the leg or arm. Since 2000, the United States has only used IPV.
- Much of the world uses the oral poliovirus vaccine (OPV).
The polio vaccine protects children by preparing their bodies to fight the poliovirus. Almost all children (more than 99 percent) are protected from polio when they get the recommended doses of the inactivated polio vaccine.
Practicing good hand hygiene and washing hands often with soap and water is also vital. Note that alcohol-based hand sanitizers do not kill poliovirus.
Wash hands with soap and water after using the bathroom, before and after eating, when hands are visibly soiled, after changing diapers, and before feeding an infant or small child.
Remember to use soap and rub your hands vigorously for 20 seconds before rinsing the soap off your hands.
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 and might improve long-term outcomes, primarily if implemented early in the illness. Healthcare providers should consult neurology and infectious disease experts to discuss possible treatments and recommend specific interventions on a case-by-case basis.
If you think you or someone in your family has symptoms of polio, please call your healthcare provider immediately or go to an emergency room.
When are you infectious (transmission period)?
An infected person can spread the virus to others immediately and up to 2 weeks after symptoms appear.
- The virus can live in an infected person’s intestines for many weeks. It can contaminate food and water in unsanitary conditions.
- People who don’t have symptoms can still pass the virus to others and make them sick.
What are the symptoms?
Most people who get infected with poliovirus will not have any visible symptoms.
About 1 out of 4 people (or 25 out of 100) with poliovirus infection will have flu-like symptoms that can include:
- Sore throat
- Stomach pain
These symptoms usually last 2 to 5 days, then go away.
A smaller proportion of people with poliovirus infection will develop other, more severe symptoms that affect the brain and spinal cord:
- Meningitis is an infection of the spinal cord or brain. Meningitis occurs in approximately 5 out of 100 people with a poliovirus infection, depending on the virus type
- Paralysis, or arm and leg weakness, occurs in 1 out of 200 people to 1 in 2000 people, depending on the virus type
Paralysis is the most severe symptom associated with poliovirus because it can lead to permanent disability and death. Between 2 and 10 out of 100 people with paralysis from poliovirus infection die because the virus affects the muscles that help them breathe.
Children who seem to recover fully can develop new muscle pain, weakness, or paralysis as adults, 15 to 40 years later. This delay in symptoms is called post-polio syndrome.
Ensure water is clean, following improved hygienic practices, and sanitation are essential for reducing the risk of transmission
Immunization is the cornerstone of polio eradication. Two types of vaccines are available:
- An inactivated poliovirus vaccine (IPV)
- A live attenuated OPV.
When to see a doctor
Check with your doctor for polio vaccination recommendations before traveling to a part of the world where polio still occurs naturally or where oral polio vaccine (OPV) is used, such as Central and South America, Africa and Asia.
Additionally, call your doctor if:
- Your child hasn’t completed the vaccine series
- Your child has an allergic reaction to the polio vaccine
- Your child has problems other than a mild redness or soreness at the vaccine injection site
- You had polio years ago and are now having unexplained weakness and fatigue
CDC Information on Polio
NJDOH Polio Provider Information Document