Risk factors for measles virus infection and susceptibility in persons aged 15 years and older in China: A multi-site case-control study, 2012-2013.

•Hospital exposure was associated strongly with measles in susceptible Chinese adults.•Approximately 20% to 40% of adult measles cases may have been acquired in hospitals.•Strengthening infection control practices is needed to reduce risk of measles.•Measles susceptibility was associated with occupation and lack of interest in SIAs.•Serological testing of controls allowed identification of transmission risk factors.