An outbreak of adult measles by nosocomial transmission in a high vaccination coverage community

With the implementation of accelerated measles elimination strategies, including maintaining high coverage rates of measles containing vaccine (MCV), employing a sensitive and specific disease surveillance system, and responding rapidly to outbreaks, the incidence of measles in Xiaoshan County has decreased drastically. It dropped to the lowest historical level in 2010 (2.82/100 000 population; the incidence was 17.29% that of 2008, which was 16.31/100 000 population), especially for children under 15 years of age. However, measles transmission has not stopped in Zhejiang Province, China. Moreover, the susceptible population now includes infants under 8 months of age who are too young to receive the MCV and adults over 20 years old. This is despite a high MCV coverage rate among children as a result of the expanded program on immunization (EPI); the reported coverage rate for the first MCV dose has been >95% since 1999. The researchers report a hospital-associated measles outbreak occurring among adults in a community of Xiaoshan County, Zhejiang Province, China. In this study they seek to identify the source and mode of transmission of measles.