Spread of respiratory infections in student dormitories in China

OBJECTIVES Student dormitory rooms in China are characterized by small space and high occupancy. This study aims to investigate infection rates for common colds and influenza among college students in a Chinese university and their association with the dormitory environment. METHODS This study involved two phases. In Phase I, 2978 students living in 998 dorm rooms in 12 buildings responded to a questionnaire survey on infections in four seasons. In Phase II, based on the data obtained from the questionnaire survey, we selected 242 dorm rooms to measure air temperature, relative humidity and CO2 concentration in both summer and winter. Ventilation rates at night were calculated based on measured CO2 concentrations. RESULTS We found that students had infections more often in winter, and in rooms with higher occupancy and dampness problems. The median value of the ventilation rate in dorm rooms in summer was 10.7 L/s per person, while it was 4.10 L/s per person in winter. There were significant associations between ventilation rate per person at night and common cold and influenza both in summer and winter (p < 0.05). A combination of dampness and low ventilation rate significantly increased the risk of common colds (adjusted odds ratios, AOR: 1.26-1.91) and influenza (AOR: 1.49-2.20). CONCLUSION College students living in a crowded dormitory room with low ventilation and dampness problems had more common colds and influenza infections.