Polio is also called poliomyelitis. It was a common disease in Sweden a hundred years ago. Mass vaccination was introduced in the late 1950s in Sweden. In the 1960s, vaccination was introduced into the general childhood vaccination program.
In 1988, the WHO launched the Global Polio Eradication Initiative. Massive international vaccination efforts have reduced the incidence of polio in the world by 99%. The American continent and Europe are now completely polio-free. In Afghanistan and Pakistan, the disease still occurs. Polio outbreaks have also been reported in recent years from some African countries as well as Syria and Iraq.
Polio is caused by a virus that only infects humans. There are three different types of polio origin – types 1, 2 and 3. It is mainly type 1 that still occurs in some parts of the world. Infection occurs via sewage-contaminated water or in close contact with an infected person. The virus causes an inflammation in the spinal cord that can lead to paralysis and sometimes breathing problems if the respiratory muscles are affected. Most recover, but respiratory care may in some cases be needed during the acute phase of the disease. Some get permanent trauma with paralysis in some body part. It usually takes seven to ten days from infection to disease symptoms. Some people who have previously had polio fall ill several years later with muscle weakness or fatigue. This condition is called postpolio.
The different polio vaccines
Some countries use a live polio vaccine. This is a vaccine taken orally. In Sweden, we use a killed vaccine that is given as an injection in the muscle of the upper arm. A basic vaccination consists of 4 doses. Children who grew up in Sweden are offered vaccines at 3, 5 and 12 months. A refill dose is given at 5-6 years of age.
If you travel to an area where a polio outbreak occurs, a refill dose is recommended. Sometimes authorities can then require that there is a documented polio vaccination that has been given 4 weeks to a maximum of one year before departure.
People who have had polio are still recommended to get vaccinated because they are only immune to the type of polio that they were once infected with.
People who have been initially vaccinated with the live oral vaccine are recommended a dose of inactivated vaccine.