Polio (also known as poliomyelitis) is a highly contagious disease caused by a virus that attacks the nervous system. Children younger than 5 years old are more likely to contract the virus than any other group.
According to the World Health Organization (WHO), 1 in 200 polio infections will result in permanent paralysis. However, thanks to the global polio eradication initiative in 1988, the following regions are now certified polio-free:
- Western Pacific
- Southeast Asia
The polio vaccine was developed in 1953 and made available in 1957. Since then cases of polio have dropped in United States.
But polio is still persistent in Afghanistan, Pakistan, and Nigeria. Eliminating polio will benefit the world in terms of health and economy. The eradication of polio can save at least $40–50 billion over the next 20 years.
It’s estimated that 95 to 99 percent of people who contract poliovirus are asymptomatic. This is known as subclinical polio. Even without symptoms, people infected with poliovirus can still spread the virus and cause infection in others.
Signs and symptoms of non-paralytic polio can last from one to 10 days. These signs and symptoms can be flu-like and can include:
- sore throat
Non-paralytic polio is also known as abortive polio.
About 1 percent of polio cases can develop into paralytic polio. Paralytic polio leads to paralysis in the spinal cord (spinal polio), brainstem (bulbar polio), or both (bulbospinal polio).
Initial symptoms are similar to non-paralytic polio. But after a week, more severe symptoms will appear. These symptoms include:
- loss of reflexes
- severe spasms and muscle pain
- loose and floppy limbs, sometimes on just one side of the body
- sudden paralysis, temporary or permanent
- deformed limbs, especially the hips, ankles, and feet
It’s rare for full paralysis to develop. Less than 1 percent of all polio cases will result in permanent paralysis. In 5–10 percent of the polio paralysis cases, the virus will attack the muscles that help you breathe and cause death.
It’s possible for polio to return even after you’ve recovered. This can occur after 15 to 40 years. Common symptoms of post-polio syndrome (PPS) are:
- continuing muscle and joint weakness
- muscle pain that gets worse
- becoming easily exhausted or fatigued
- muscle wasting, also called muscle atrophy
- trouble breathing and swallowing
- sleep apnea, or sleep-related breathing problems
- low tolerance of cold temperatures
- new onset of weakness in previously uninvolved muscles
- trouble with concentration and memory
Talk to your doctor if you’ve had polio and are starting to see these symptoms. It’s estimated that 25 to 50 percent of people who survived polio will get PPS. PPS can’t be caught by others having this disorder. Treatment involves management strategies to improve your quality of life and reduce pain or fatigue.
As a highly contagious virus, polio transmits through contact with infected feces. Objects like toys that have come near infected feces can also transmit the virus. Sometimes it can transmit through a sneeze or a cough, as the virus lives in the throat and intestines. This is less common.
People living in areas with limited access to running water or flush toilets often contract polio from drinking water contaminated by infected human waste. According to the Mayo Clinic, the virus is so contagious that anyone living with someone who has the virus can catch it too.
Pregnant women, people with weakened immune systems — such as those who are HIV-positive — and young children are the most susceptible to the poliovirus.
If you have not been vaccinated, you can increase your risk of contracting polio when you:
- travel to an area that has had a recent polio outbreak
- take care of or live with someone infected with polio
- handle a laboratory specimen of the virus
- have your tonsils removed
- have extreme stress or strenuous activity after exposure to the virus
Your doctor will diagnose polio by looking at your symptoms. They’ll perform a physical examination and look for impaired reflexes, back and neck stiffness, or difficulty lifting your head while lying flat.
Labs will also test a sample of your throat, stool, or cerebrospinal fluid for the poliovirus.
Doctors can only treat the symptoms while the infection runs its course. But since there’s no cure, the best way to treat polio is to prevent it with vaccinations.
The most common supportive treatments include:
- bed rest
- antispasmodic drugs to relax muscles
- antibiotics for urinary tract infections
- portable ventilators to help with breathing
- physical therapy or corrective braces to help with walking
- heating pads or warm towels to ease muscle aches and spasms
- physical therapy to treat pain in the affected muscles
- physical therapy to address breathing and pulmonary problems
- pulmonary rehabilitation to increase lung endurance
In advanced cases of leg weakness, you may need a wheelchair or other mobility device.
The best way to prevent polio is to get the vaccination. Children should get polio shots according to the vaccination schedule presented by the Centers for Disease Control and Prevention (CDC).
CDC vaccination schedule
|2 months||One dose|
|4 months||One dose|
|6 to 18 months||One dose|
|4 to 6 years||Booster dose|
Polio vaccine prices for children
On rare occasions these shots can cause mild or severe allergic reactions, such as:
- breathing problems
- high fever
- swelling of throat
- rapid heart rate
Adults in the United States aren’t at high risk for contracting polio. The greatest risk is when traveling to an area where polio is still common. Make sure to get a series of shots before you travel.
Polio vaccinations around the world
Overall, cases of polio have dropped by 99 percent. Only 74 cases were reported in 2015.
Polio still persists in Afghanistan, Pakistan, and Nigeria.
Polio is a highly contagious virus that can result in spinal cord and brainstem paralysis. It most commonly affects children under 5 years old. Cases of polio peaked in the United States in the 1952 with 57,623 reported cases. Since the Polio Vaccination Assistance Act, the United States has been polio-free since 1979.
While many other countries are also certified polio-free, the virus is still active in countries that haven’t started immunization campaigns. According to WHO, even one confirmed case of polio puts children in all countries at risk.
Afghanistan is set to start its immunization campaign for early October and November of 2016. National and Subnational Immunization Days are planned and ongoing for countries in West Africa. You can stay up to date with case breakdowns on The Global Polio Eradication Initiative’s website.