Poliovirus neutralizing antibody persistence after vaccination with the Sabin vaccine: a follow-up study.

In 1976, a cohort survey on the persistence of neutralizing antibodies in children regularly immunized 1 to 4 years earlier with the Sabin attenuated vaccine (OPV) was undertaken in the Venice mainland. Subsequent serological evaluations in the same cohort were carried out in 1983 and 1993. A macroneutralization test using a 1:4 initial serum dilution was utilized in the 1976 and 1983 survey years.

Immunity status to poliovirus in Veneto region (north-east Italy). A seroepidemiological survey.

The immunity state to poliovirus types 1, 2, and 3 of a population aged 2 to 75 years was determined by examining 274 sera collected in the Venice mainland (North-East Italy). Altogether, the neutralizing antibody prevalences (at a titre > or = 1:2) for poliovirus 1, 2, and 3 were 99.0 percent (geometrical mean titres [GMT]: 72.

Persistence of poliovirus-neutralizing antibodies 2-16 years after immunization with live attenuated vaccine. A seroepidemiologic survey in the mainland of Venice.

A seroepidemiological survey was conducted on subjects who had received a full vaccination course with live attenuated poliovirus 2-16 years before. For strains 1 and 2 prevalence of seropositives and median values dropped gradually during the first 10 years; strain 3 showed a much earlier decline. Environmental displacement of wild poliovirus by the attenuated, less immunogenic strain might eventually induce a 'gap', should complacency hamper needed vaccination efforts.

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.

Hepatitis B vaccine: immune response in student nurses. A fifteen-month follow-up.

The authors describe a 15-month follow-up of twenty-nine nurse students vaccinated against hepatitis B with Hevac B Pasteur. At three months all subjects were anti-HBs positive, with a geometric mean titre (GMT) of 1187 mIU/ml. At the time of booster dose (T14) GMT had fallen to 380 mIU/ml; after one month (T15) GMT had risen again to 9332 mIU/ml.