Poliomyelitis (polio) is a very contagious disease caused by a virus. Most children who are infected with polio have no symptoms. A few have mild symptoms. The virus is most known for attacking the nervous system and causing paralysis. But very few children with polio develop paralysis. Polio is now very rare in the U.S. because children are vaccinated against it.
Polio is caused by poliovirus. There are 3 types of the virus. It usually spreads through contact with infected feces (stool). This often happens when children don't wash their hands or don't wash them properly. It can also happen from eating or drinking food or water that contains the virus. It can be spread when an infected child coughs or sneezes infected droplets into the air. The virus can also be in a child’s stool for several weeks. Children are most contagious right before and right after symptoms start.
A child is more at risk for polio if he or she is in an area where polio is still active. Polio is not active in the U.S. But polio is still a problem in developing countries that have widespread poverty and less access to the polio vaccine. This includes a few countries in Africa and Asia. International medical groups work to get more people vaccinated to get rid of the polio virus worldwide. A child is at risk if he or she travels to any of these areas, or has contact with someone else who has. Polio is especially a risk for babies and children during the summer and autumn in these areas.
Before traveling to countries where polio is active or at risk for outbreaks, check with the CDC.
Most children with polio have no symptoms at all. This is called an inapparent infection. The other types of polio are:
- Abortive. This is a mild illness that doesn’t last a long time.
- Nonparalytic. This is also a milder illness that doesn’t last a long time.
- Paralytic. This illness can cause severe symptoms and long-term problems.
Symptoms can occur a bit differently in each child.
The most common symptoms of abortive polio can include:
- Less appetite than normal
- Nausea and vomiting
- Sore throat
- Not feeling well all over (malaise)
- Belly pain
The most common symptoms of nonparalytic polio can include the same symptoms as abortive. Then after symptoms start to go away, the child may have:
- Pain of the muscles in the neck, torso, arms, and legs
- Stiffness in the neck and along the spine
The symptoms for paralytic polio are the same as above. They can also include:
- Muscle weakness all over
- Severe constipation
- Bladder paralysis
- Muscle wasting
- Weakened breathing
- Weak cough
- Hoarse voice
- Trouble swallowing
- Muscle paralysis that may be permanent
- Irritability and anger
Most children who have paralysis will get some of their strength back over time. Some children will return to normal. A small number of children will die from the disease.
The symptoms of polio can be like other health conditions. Make sure your child sees his or her healthcare provider for a diagnosis.
The healthcare provider will ask about your child’s symptoms and health history. He or she may also ask about your recent travel to countries where polio is active. He or she will give your child a physical exam. Your child may also need tests. They may include:
- Virus cultures. The healthcare provider will take samples of stool, and of fluid from the throat. Viruses from the samples are grown in a lab and checked with a microscope.
- Blood test. This is done to check for polio antibodies.
- Spinal tap (lumbar puncture). The healthcare provider puts a needle into the lower back, into the spinal canal. This is the area around the spinal cord. The pressure in the spinal canal and brain can then be measured. The provider removes a small amount of cerebral spinal fluid (CSF) and sends it for testing to find out if there is an infection or other problems. CSF is the fluid that surrounds your child's brain and spinal cord.
There is no medicine to cure the virus, but treatment is done to help aid a child’s comfort and recovery from the virus. This is called supportive treatment. This kind of treatment may include:
- Pain medicine such as acetaminophen
- Bed rest until fever is lower
- A healthy diet
- Very little physical activity
- Hot packs or heating pads for muscle pain
Possible complications of paralytic poliomyelitis can include permanent paralysis of certain muscle groups. This may include the leg muscles, or the muscles used for breathing.
The vaccine is the main way to prevent polio. In the U.S., children are given inactivated polio vaccine (IPV). This is given by a shot. IPV can’t cause polio. It’s safe for a child with a weak immune system. Oral poliovirus vaccine (OPV) is no longer given in the U.S. OPV contains a live virus and may be less safe than IPV for some children.
The IPV polio vaccine is given at these ages:
- 2 months
- 4 months
- Between 6 and 18 months
- Between ages 4 and 6
Your child may need a polio booster within 12 months before travel to a country where polio is active. Before traveling to countries where polio is active or at risk for outbreaks, it is helpful to check with the CDC.
When to Call a Healthcare Provider
Call the healthcare provider if:
- Your child has not had the full series of polio vaccines
- You are planning travel to a country with polio
- You have been to a country with polio and your child has symptoms
- Your child had close contact with a person sick with polio
- Polio is a very contagious disease caused by a virus. Polio is now very rare in the U.S. because of the polio vaccine.
- Most children who are infected with polio have no symptoms. A few have mild symptoms. In rare cases, the illness can cause severe symptoms and long-term problems.
- The virus usually spreads through contact with infected feces (stool). It can be spread when an infected child coughs or sneezes infected droplets into the air.
- A child is more at risk for polio if he or she is in an area where polio is still active. Polio is still a problem in developing countries that have widespread poverty and less access to the polio vaccine.
- There is no medicine to cure the virus, but treatment is done to help aid a child’s comfort and recovery from the virus. This is called supportive treatment.
- The vaccine is the main way to prevent polio. Your child may need a polio booster within 12 months before travel to a country where polio is active.
Tips to help you get the most from a visit to your child’s healthcare provider:
- Know the reason for the visit and what you want to happen.
- Before your visit, write down questions you want answered.
- At the visit, write down the name of a new diagnosis, and any new medicines, treatments, or tests. Also write down any new instructions your provider gives you for your child.
- Know why a new medicine or treatment is prescribed and how it will help your child. Also know what the side effects are.
- Ask if your child’s condition can be treated in other ways.
- Know why a test or procedure is recommended and what the results could mean.
- Know what to expect if your child does not take the medicine or have the test or procedure.
- If your child has a follow-up appointment, write down the date, time, and purpose for that visit.
- Know how you can contact your child’s provider after office hours. This is important if your child becomes ill and you have questions or need advice.