The incidence of rubella virus infections in Switzerland after the introduction of the MMR mass vaccination programme.

We have collected data on the incidence of rubella in Switzerland from 1987 to 1992 to help evaluating the impact of the measles, mumps and rubella (MMR) mass vaccination programme which started in 1985 in this country. We used detailed informations on samples submitted for diagnostic testing in conjunction with anonymous laboratory notifications to the Swiss Federal Office for Public Health, and data from the Swiss sentinel network of general practitioners to find trends in the incidence of rubella after the introduction of mass vaccination. We observed an unabated seasonal oscillation without decreasing trend during the observation period and were unable to detect a shift in the age distribution of cases. An important proportion of laboratory-confirmed rubella occurred in women of childbearing age. Immigrants from regions with low endemicity of rubella were at increased risk of contracting rubella and transmitting it to their offspring. We conclude, that MMR mass vaccination has not interrupted the circulation of rubella virus in Switzerland, and that improvements in the implementation and surveillance of the MMR vaccination campaign are necessary in order to avoid untoward effects of it.