Measles cases 1944-1963 followed a highly variable epidemic pattern, with 150,000-850,000 cases reported per year. A sharp decline followed introduction of the first measles vaccine in 1963, with fewer than 25,000 cases reported in 1968. Outbreaks around 1971 and 1977 gave 75,000 and 57,000 cases, respectively. Cases were stable at a few thousand per year until an outbreak of 28,000 in 1990. Cases declined from a few hundred per year in the early 1990s to a few dozen in the 2000s.