Evaluation of the national immunisation programme in the Netherlands: immunity to diphtheria, tetanus, poliomyelitis, measles, mumps, rubella and Haemophilus influenzae type b.

The immunity to vaccine-preventable diseases included in the Dutch immunisation programme in the general population and among orthodox reformed individuals who refuse vaccination was assessed. The programme induces good protection. However, a large proportion of adults lacks diphtheria and tetanus immunity. Measles, mumps and rubella seroprevalence was somewhat lower among vaccinated compared to unvaccinated cohorts. The prevalence of HibPS antibodies declined during 2.5 years after the fourth vaccination. However, protection occurs also by memory immunity. Herd immunity is sufficient among the general population, but not among orthodox reformed individuals. Immunosurveillance is an efficient way to evaluate the effects of immunisation programmes and identify risk groups for infection.