What is Polio?


Polio is mainly a disease of children and young adults caused by polio enterovirus type 1, 2 or 3. This once much feared illness occurred in numerous epidemics.  The last great polio epidemics plagued Ireland in the mid 1950s, as well as the rest of Europe and America.

The inactivated polio vaccine (IPV) was developed by Jonas Salk in late 1955 and the oral polio vaccine (OPV), became available in 1962 following the work of Albert Sabin.  The widespread use of these vaccines has made acute polio in the developed world a rarity.

It is estimated that there are approximately 7,000 survivors of polio living in the Republic of Ireland at present. Most of these people are middle aged or becoming elderly.


Polio is caused by an enterovirus of high infectivity whose main route of infection is via the human gastrointestinal tract. Infection is oral and the virus multiplies in the gut for one to three weeks, after which the person either recovers or becomes very ill. Infection rates are very high but the vast majority of patients show no symptoms or appear as if they have a flu-like illness.