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 7,500 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.