[Measles, mumps and rubella: vaccination rate and seroprevalence in 8th grade students of 8 different sites in Switzerland 1995/96].

In 1987, the Swiss Federal Health Office (BAG) and the Swiss cantons launched the MMR-vaccination campaign. Within the frame of the SCARPOL Study, the vaccination status of 649, 8th class students was registered and serum samples were collected. The measles, mumps and rubella specific antibody levels were determined. The vaccination rate was 84% for measles, 74% for mumps, and 62% for rubella, 55% of these children had been vaccinated with the combined vaccine MMR. The vaccination rate for the different study areas varied from 70% to 95% for measles, 42% to 94% for mumps and 18% to 89% for rubella, 92% of the children tested seropositive for measles specific antibodies, 87% for mumps and 84% for rubella. The seroprevalence for measles, mumps and rubella was significantly higher for vaccinated than for unvaccinated children. Non-Swiss children had, without exception, a higher seroprevalence rate than Swiss children. Undergoing the disease did not influence the seroprevalence for measles, but it did so for mumps and rubella, for vaccinated and unvaccinated children alike. By analysis according to study site, we observed that sites with higher vaccination rates (e.g. Grabs in Rheintal) sometimes showed a lower seroprevalence than sites with lower vaccination rates (e.g. Langnau). This was the case for all three vaccines. This, together with other observations, shows that a booster is necessary for an adequate immunisation--as a wild virus infection or as a second vaccination.