Measles outbreak on a college campus transmitted through internet cafés.

Abstract

During March 2008, a college in Urumqi, capital of Xinjiang Uygur Autonomous Region in China, reported a measles outbreak, amid a city-wide outbreak involving >2700 cases. Suspected case patients were defined as patients with onset of fever (≥38°) and rash between 7 March and 30 April 2008. Probable case patients were defined as suspected case patients with >3 days of rash or known exposure to someone with laboratory-confirmed measles. Confirmed case patients were defined as suspected or probable case patients with Koplik spots or positive titer for immunoglobulin M antibody. We conducted a case-control investigation to identify risk factors for transmission. We identified 162 suspected (attack rate, 1.9%), 99 probable, and 62 confirmed case patients. The epidemic curve indicated a point source initially, followed by person-to-person transmission. Approximately 63% of 90 probable case patients and 27% of 150 asymptomatic student controls randomly selected among classmates of student case patients visited internet cafés during the exposure period (odds ratio [OR], 4.5; 95% confidence interval [CI], 2.6-8.0); 66% of case patients and 45% of student controls reported close contact with a measles case patient (OR, 2.3; 95% CI, 1.3-3.9). In stratified analysis, visiting internet cafés (OR, 4.0; 95% CI, 1.5-11) remained significantly associated with disease, but contact with case patients (OR, 1.9; 95% CI, .79-4.4) became nonsignificant. This measles outbreak was transmitted in internet cafés, followed by secondary transmission. Chinese universities should require proof of immunity or 2 doses of measles vaccine at college entry.