Measles, Mumps, and Rubella - Centers for Disease Control and ...

Vol. 47 / No. RR-8 MMWR 5Rubella EliminationBefore rubella vaccine was licensed during 1969, rubella incidence was greatestamong preschool and elementary school children. Therefore, vaccination campaignsinitially targeted children in kindergarten and the early grades of elementaryschool, with the aim of interrupting circulation of the virus and eliminating the risk forexposure among susceptible pregnant women. The risks associated with administeringa potentially teratogenic live virus vaccine to young women of childbearing agewere not known. During 1969–1976, reported rubella cases decreased from 57,600 to12,400. However, during 1975–1977, 62% of reported rubella cases occurred amongpersons aged >15 years compared with 23% of cases occurring during 1966–1968,and serologic studies suggested that 10%–15% of adults remained susceptible to rubella(20 ).The number of CRS cases reported nationwide decreased by 69% from 69 in 1970to 22 in 1976. Rubella outbreaks continued to occur among older adolescents andyoung adults (e.g, in military camps, high schools, colleges, and universities). In 1977,ACIP modified its recommendations to include the vaccination of susceptible postpubertalgirls and women. During the same year, the DHEW undertook the NationalChildhood Immunization Initiative, which sought to immunize >90% of the nation’schildren against all vaccine-preventable diseases. Enforcement of requirements forvaccination before school entry was part of the initiative. The number of reported rubellaand CRS cases decreased after these programs were implemented, from 20,395rubella cases and 29 CRS cases in 1977 to 752 rubella cases and 2 CRS cases in 1984.In 1988, 225 cases of rubella were reported in the United States, the fewest since nationalreporting began.However, because of outbreaks among unvaccinated adults (e.g., in prisons, colleges,and workplaces), >1000 rubella cases were reported in 1990 and again in 1991.The largest outbreak and the greatest number of CRS cases occurred among childrenand adults in religious communities that do not accept vaccination. Since 1992, reportedindigenous rubella and CRS have continued to occur at a low but relativelyconstant endemic level with an annual average of