RESUMEN
In 1998, the Advisory Committee on Immunization Practices and the American Academy of Pediatrics recommended that states ensure that all children in grades kindergarten through 12 receive 2 doses of measles-mumps-rubella (MMR) vaccine by 2001. In 2000, the National Immunization Program surveyed states, the District of Columbia, and United States territories, commonwealths, and protectorates to assess progress toward this goal. Almost all respondents (53 [98%] of 54) reported a second-dose requirement for entry to elementary school, middle school, or both. By fall of 2001, most (82%) school-aged children in the United States were in grades requiring a second dose of measles vaccine. For 29 responding programs, the requirement did not yet affect all grades. By 2009, 52 of 54 responding programs will require a second dose for all grades. Although not all states have achieved coverage of all schoolchildren with 2 doses of MMR vaccine, most states are well on their way toward this goal.