Virus: Polio (enterovirus C)
Poliomyelitis (polio) is a highly infectious disease that is caused by an enterovirus. The virus invades the nervous system and lives in the throat and intestinal tract of those who are infected.
The virus spreads from person to person via infected stool or oral/nasal secretions from the infected individual entering the body of a non-infected individual through the mouth.
Polio often does not cause serious illness, and many times people infected with polio display no symptoms of the disease. In fact, about 72% of those infected will have no symptoms.2
About 24% of people infected with polio will develop minor symptoms including: Fever, fatigue, nausea, headache, flu-like symptoms, and/or pain in the limbs.2 All of the symptoms tend to resolve completely.
Who is at Risk:
Those who have not been vaccinated are at risk, especially small children/infants and the elderly.
Also, those in the following groups are at increased risk:
- You are traveling to a polio-endemic or high-risk area of the world: Currently the countries where polio is endemic are Afghanistan, Nigeria, and Pakistan. It also continues to get re-introduced into what’s called the “poliovirus importation belt”, which include countries from west Africa to the Horn of Africa, Cameroon, and Syria.2,5
- You work in a lab handling specimens that might contain polioviruses.
- Or you are a health care workers who have close contact with a person who could be infected with the poliovirus.
Adults that fall into these increased risk groups and who have been fully vaccinated against polio can receive one lifetime polio booster of IPV and be considered protected.
In about 1% of those infected, polio may cause paralysis—inability to move arms and legs (most often the legs). It also can cause permanent disability, meningitis, and even death due to the paralization of muscles that help the body breathe. For those who develop paralysis, about 5-10% die due to paralysis of the respiratory muscles.2 This death rate increases with age.
When polio was common in the U.S., it paralyzed and killed thousands of people every year.3
Pregnancy/Unborn Child/Newborn Risk:
Pregnant women should avoid the vaccine, however there have been no reported side effects in pregnant women who have received the vaccine.
Getting vaccinated is the only way to prevent getting polio.
There are two types of polio vaccines: the inactivated polio vaccine (IPV) and the oral polio vaccine (OPV). OPV is made from the live poliovirus. It is considered to be highly effective at preventing polio disease, however a few cases a year of polio were seen, caused by the vaccine itself. The IPV is made using an inactivated (dead) virus, which is unable to cause polio.
The oral version of the vaccine has not been used in the United States since 2000, however it is still used throughout a lot of the world. The IPV is the only polio vaccine given in the U.S. It is given as an injection in the arm or leg, depending on the patient’s age—in the leg for most children.
Nowadays, most everyone gets the polio vaccine during childhood. It is recommended that children get four doses of IPV: One at 2 months, one at 4 months, one between 6 and 18 months, and finally a booster between 4 and 6 years of age.
It is safe for IPV to be given at the same time as other vaccines, and it often is given along with other vaccines, as recommended in the childhood vaccine schedule.1
If you have never been vaccinated against polio, you should consider getting three doses of IPV. The first dose may be given at any time. The second will be given 1-2 months later, and the third will be given 6-12 months after the second dose.
If you have had several doses of the polio vaccine, but are not fully vaccinated, it is important to get the booster doses. It doesn’t matter how long it’s been since your last dose.
Unfortunately there is no cure for polio. Bed rest, pain relievers, portable ventilators to assist breathing, and physical therapy are among supportive treatments used in keeping the patient comfortable and speeding recovery.
Many people recover completely and fewer than 25% of people infected with polio are disabled from it.
Some Great Links:
- “Rotarians Make Fight Against Polio Their Own.” The rotarian Magazine
- On this Day: Polio Vaccine Introduced to British Public in Bid to Eradicate 20th Century Plague
- Polio Children.org (Children living with polio-related disabilities)