Estimating the Number of Measles-Susceptible Children and Adolescents in the United States Using Data From the National Immunization Survey-Teen (NIS-Teen).

Tuesday, 19th of July 2016

Am J Epidemiol. 2016 Jul 15;184(2):148-56. doi: 10.1093/aje/kwv320. Epub 2016 Jun 23.

Estimating the Number of Measles-Susceptible Children and Adolescents in the United States Using Data From the National Immunization Survey-Teen (NIS-Teen).

Bednarczyk RA, Orenstein WA, Omer SB.

Abstract

Despite high measles vaccination rates in the United States, imported measles cases have led to outbreaks in the United States. These outbreaks have not led to sustained measles transmission; however, with each birth cohort of children not fully vaccinated against measles, measles-susceptible individuals accumulate in the population. The total number of measles-susceptible children and adolescents in the United States is unknown. We used age-specific measles vaccination data from the National Immunization Survey-Teen (2008-2013) to estimate the number of measles-susceptible children aged 17 years or younger, accounting for vaccine effectiveness, infant protection from maternal antibodies, and loss of immunity following childhood cancer treatment. Approximately 12.5% of US children and adolescents are susceptible to measles, with the highest levels of susceptibility being observed in children aged 3 years or younger (24.7% are susceptible to measles). In sensitivity analyses, we found that a sustained decrease in measles vaccination coverage from 91.9% (2013 level) to 90.0% (2009 level) would add nearly 1.2 million susceptible children and adolescents (thus making 14.2% of those aged 17 years or younger susceptible to measles). This reemphasizes the need for high measles vaccination coverage to support population-level immunity and prevent reestablishment of indigenous measles transmission in the United States.