Measles imported by returning U.S. travelers aged 6-23 months, 2001-2011.

In the first 2 months of 2011, CDC received reports of seven imported measles cases among returning U.S. travelers aged 6-23 months; four required hospitalization. Young children are at greater risk for severe measles, death, or sequelae such as subacute sclerosing panencephalitis. Although all seven children had been eligible for vaccination before travel, none had received measles, mumps, and rubella (MMR) vaccine, the only measles-containing vaccine currently available in the United States. To characterize imported measles cases reported in the first 2 months of 2011 in U.S. travelers aged 6-23 months and compare them with cases in recent years, CDC analyzed data from the National Notifiable Diseases Surveillance System (NNDSS) for the period January 2001-February 2011. The results of that analysis indicated that, during January-February 2011, a total of 13 imported cases were reported in U.S. residents, including the seven children aged 6-23 months. During 2001-2010, a total of 159 imported cases were reported in U.S. residents, including 47 (range: 3-8 per year) in children aged 6-23 months (three of whom had been vaccinated before travel). Because measles remains endemic in much of the world, international travelers should be up-to-date on vaccinations. In accordance with the Advisory Committee for Immunization Practices (ACIP) recommendations, U.S. children who travel or live abroad should be vaccinated at an earlier age than those living in the United States because of the greater risk for exposure to measles outside the United States, and particularly outside the Americas.