Experiences of vaccination with inactivated poliovirus vaccine and epidemiology round a single case of polio in 1977 in Sweden.

Inactivated poliovaccine manufactured in this country has been used in Sweden since 1957. The coverage of the vaccination in children is close to 100%. The majority of adults has also been immunized. No indigenous case occurred between 1962 and 1977. In 1977 a 2-year-old unvaccinated girl caught a mild paralytic disease caused by polio type 2. An epidemiologic investigation revealed excretion of virus in 25 persons, all close contacts to other excretors. No virus excretors were found among vaccinated pre-school children while 14 of 20 unvaccinated children showed positive virus samples.