Evaluatie van het Rijksvaccinatieprogramma: immuniteit van de Nederlandse bevolking tegen difterie, tetanus en poliomyelitis

To assess the immunity to diphtheria, tetanus and poliomyelitis in the Dutch population and among orthodox reformed individuals refusing vaccination.

Design

Cross-sectional study.

Methods

An sample of 40 municipalities was drawn proportional to their size in 1995/’96. In addition, 8 municipalities with low vaccine coverage were chosen to have access to orthodox reformed individuals. In each municipality an age-stratified sample was drawn of 380 persons (0-79 years). Participants were asked to give a blood sample and to fill out a questionnaire. Sera were tested with the Toxin Binding Inhibition assay for tetanus and diphtheria antibodies (nationwide sample: n = 7715; orthodox reformed individuals: n = 233) and with the neutralisation test for poliovirus type 1, 2 and 3 antibodies (n = 7773 and n = 236).

Results

In the nationwide sample the prevalences of diphtheria and tetanus antibodies (≥ 0.01 IU/ml) were 88 and 86. In at least 90 antibodies (titre ≥ 1:8) against poliovirus type 1, 2 or 3 were measured. For those under 50 years the prevalences were high, but for diphtheria and tetanus the prevalence decreased for individuals aged 50 years or over. Among orthodox reformed individuals 40, 60, 65, 59 and 69 had antibodies against diphtheria, tetanus, poliovirus type 1, 2 and 3, respectively.

Conclusion

The National Immunisation Programme induces long-term diphtheria, tetanus and poliomyelitis immunity. Adults are well protected against poliomyelitis. However, a large number of adults lacks diphtheria and/or tetanus antibodies. Introduction of Corynebacterium diphtheriae or poliovirus in sociogeographically clustered orthodox reformed groups might constitute a danger for spread of these pathogens.