Prevalence of poliovirus neutralizing antibodies. A seroepidemiologic survey of vaccinated and unvaccinated women of fertile age.

The Authors tested a group of 232 women of fertile age, living in the Venice mainland, for presence of detectable protective serum antibodies against poliovirus strains 1, 2 and 3, according to vaccination status with living, attenuated poliovirus. Overall, unvaccinated subjects had a slightly higher prevalence of seropositivity as well as higher geometric mean titres than the women who had undergone a full vaccination course fifteen to twenty years before. Particularly worrisome was lack of protection against poliovirus 3, found in 23% of vaccinated and 15% of unvaccinated study participants. Break in herd immunity might end up in localized outbreaks of poliomyelitis, a not too distant possibility in Italy, where a steady flow of immigrants from North Africa and the Near East provide a source of wild poliovirus strains.