[Status of immunity against poliomyelitis in Germany]

Is EU/EEA population protected from polio?

The WHO European Region has been declared polio-free since 2002. By 2010, inactivated polio vaccine (IPV) was the only polio vaccine in use in the EU/EEA for the primary vaccination of children. A systematic review of the literature on polio seroprevalence studies, complemented by the analysis of available vaccine coverage data, has been carried out with the aim of assessing the level of protection against polio in the European population. A total of 52 studies, with data from 14 out of the 31 EU/EEA countries, were included in the analysis. This systematic review shows that, overall, seroprevalence for PV1 and PV3 is high in most countries, although seroimmunity gaps have been detected in several birth cohorts. In particular, relatively low immunity status was found in some countries for individuals born in the 60's and 70's. Discrepancies between reported vaccination coverage and immunity levels have been also highlighted. Countries should make sure that their population is being vaccinated for polio to reduce the risk of local poliovirus transmission in case of importation. Moreover, assessing immunity status should be priority for those traveling to areas where wild polioviruses are still circulating.

Immunity status against poliomyelitis in persons 13-14 years old living in Rome

The immunity against poliomyelitis in 1000 subjects 13-14 years old was evaluated. Neutralizing antibodies against poliovirus type 1, 2 and 3 were detected in 97.6%, 95.8% and 70% of samples, respectively. 3/1000 (0.3%) subjects were simultaneously seronegative to the three types. WHO does not suggest a protective level of International Units (IU), but our data indicate that such level is 0.45 IU for polio type 1, 0.65 IU for the type 2 and 0.138 for the type 3. A booster dose of vaccine in adolescence to ensure personal and herd immunity is recommended.

Quantitative detection of neutralizing antibodies against polioviruses and non-polio enteroviruses (NPEV) using an automated microneutralization assay: a seroepidemiologic survey

A seroepidemiological survey for the assessment of immunity against polioviruses and non-polio enteroviruses (NPEV) seroprevalence was performed using a recently established automated microneutralization assay. The seroprevalences of neutralizing antibodies against Coxsackie viruses B1-B6, and A9, echoviruses 6, 9, 11, and 30, and polioviruses 1, 2, and 3 were investigated in serum samples collected over a period of 30 months (January 1990 to June 1992). Overall, NPEV seroprevalence ranged from 8.3% (Coxsackie virus B6) to 69.8% (echovirus 30). Age-related increases of seroprevalence were only observed for Coxsackie viruses B2 and A9. Relatively low antibody titres were found, the average antibody titre being the highest for Coxsackie virus B2 (1/55.4). The overall poliovirus seropositivity rate reached 80%. The highest seroprevalence was observed in the higher age groups (> or = 50 years). A relatively high proportion (7%) of individuals did not show neutralizing antibodies against all the three poliovirus serotypes. The results of our study have shown that, using an automated microneutralization assay, it is possible to perform seroepidemiological surveys in large patient populations. Until now, no comparable study concerning the NPEV seroprevalence has been performed.

Immunity from diphtheria, tetanus, poliomyelitis, measles, mumps and rubella among adults in Lithuania

Health authorities have estimated a low immunity level against diphtheria, tetanus, poliomyelitis, measles, mumps and rubella among adults in Lithuania due to less than optimal vaccine quality. The aim of this study was to evaluate the level of immunity by blood sampling 100 young women, 50 young men and 50 middle-aged men and from the immunization history by questionnaire. Lack of protection against diphtheria was found in 0%, 2% and 46% of the young women, young men and middle-aged men respectively. The corresponding data for tetanus were 0%, 0% and 10%. It was found that 85% of the women had antibodies to all 3 types of polioviruses vs. 80% of the young men and 56% of the middle-aged men. A sub-protective antibody level against measles was found in 12% of the women, 22% of the young men, but in none of the middle-aged men. A protective titre of rubella antibodies was found among 94% of the young, pregnant women. It can be concluded that the level of immunity in Lithuania is comparable to that in Western Europe for the same age groups and that the launching of adult vaccination programs in Eastern Europe should be preceded by sero-epidemiological studies.