Epidemiology of rubella in Finland.

Before rubella vaccination programmes began, rubella infection was prevalent in Finnish children. The disease occurred as epidemics at intervals of a few years. Rubella infection was most often contracted between the ages of 2 and 12 years. Vaccinations specifically aimed at eradicating rubella were begun with monocomponent vaccine in the mid-1970s, and the measles, mumps and rubella (MMR) vaccination programme with two injections got underway in 1982. A clear reduction in rubella cases was evident a few years after the launch of the MMR programme. Owing to a sufficiently high vaccination coverage (>95% since 1987), circulation of the indigenous rubella virus in the Finnish population ceased in the late 1990s. Some rubella cases have been imported to Finland since elimination, but they have not caused any secondary cases. This shows unambiguously that protection against rubella continues to be effective, although our cohort studies imply that the vaccine induced antibody levels do decrease with time. The MMR programme has also eliminated congenital rubella syndrome (CRS) from the country. The last CRS case was recorded in 1986. As a result of the high coverage two dose MMR vaccination programme, rubella was successfully eliminated from Finland. How long the acquired protection will last remains to be seen.