Outbreak of measles--San Diego, California, January-February 2008

Measles, once a common childhood disease in the United States, can result in severe complications, including encephalitis, pneumonia, and death. Because of successful implementation of measles vaccination programs, endemic measles transmission has been eliminated in the United States and the rest of the Americas. However, measles continues to occur in other regions of the world, including Europe. In January 2008, measles was identified in an unvaccinated boy from San Diego, California, who had recently traveled to Europe with his family. After his case was confirmed, an outbreak investigation and response were initiated by local and state health departments in coordination with CDC, using standard measles surveillance case definitions and classifications. This report summarizes the preliminary results of that investigation, which has identified 11 additional cases of measles in unvaccinated children in San Diego that are linked epidemiologically to the index case and include two generations of secondary transmission. Recommendations for preventing further measles transmission from importations in this and other U.S. settings include reminding health-care providers to 1) consider a diagnosis of measles in ill persons who have traveled overseas, 2) use appropriate infection-control practices to prevent transmission in health-care settings, and 3) maintain high coverage with measles, mumps, and rubella (MMR) vaccine among children.