Mass vaccination programme aimed at eradicating measles, mumps and rubella in Sweden: vaccination of schoolchildren.

In 1982-83, a unique, two-dose programme of immunization with a combined vaccine against measles, mumps and rubella was initiated in Sweden. The first dose was administered at 18 months and the second at 12 years of age. A vaccination study was carried out on 247 12 year old schoolchildren from four schools situated in two urban and two rural areas. In urban areas, 30% of children were found to be susceptible to rubella and 18% to mumps, compared with 55% susceptible to rubella and 31% to mumps in rural areas. The reverse was found for measles, to which 20% of children lacked immunity in urban areas but only 6% in rural areas. Seroconversion was seen in 82% against measles, in 80% against mumps and in 100% against rubella. Follow-up studies of the timing and the virus dosage are also to be carried out.