Poliomyelitis in the Netherlands 1958-69: the influence of a vaccination programme with inactivated poliovaccine.

The Netherlands is one of the few countries where poliomyelitis vaccination is practised with inactivated vaccine. Vaccinations started in 1957 and since 1962 have been carried out with a diphtheria-tetanus-pertussis-poliomyelitis vaccine according to a fixed schedule. The overall acceptance rate has been over 90%.Since 1957 the poliomyelitis morbidity has decreased by more than 99% in fully vaccinated persons and by 60-80% among nonvaccinated persons. The latter reduction probably resulted from a decrease in the amount of virus circulating after the vaccination campaign had started. The rather unequal distribution of acceptance rates allowed for a more detailed examination, which showed a relation between acceptance rates and morbidity figures. The morbidity pattern is now characterized by a few local outbreaks among nonvaccinated subjects in areas with low vaccination rates, and by the virtual disappearance of the disease in the rest of the country.