Measles in the United Kingdom 1990-2008 and the effectiveness of measles vaccines.

We identified all children in the UK General Practice Research Database diagnosed with measles from 1990 to 2008 and calculated annual incidence according to age and geographic region by dividing the number of cases per year by the number of children who were active in the population. We evaluated the effectiveness of the measles vaccines by comparing the vaccination histories of children who were diagnosed with measles (cases) to children who were not (controls). The annual incidence of measles fell after the introduction of the MMR vaccine in late 1988. However, a modest outbreak of measles occurred in 1994, leading to large nationwide programs to immunize children. Since 1996, the incidence of measles has fallen by more than 80%. Prior measles vaccination is highly effective and has substantially reduced the risk of measles.