Spread of respiratory infections in student dormitories in China

Childhood pneumonia in Beijing: Associations and interactions among selected demographic and environmental factors

Among infectious diseases, pneumonia is the greatest cause of mortality in children less than 5 years old. Approximately 27% of Beijing's 3-8 year-old children have had pneumonia at least once. The sole reservoir of pneumonia pathogens is the human nasopharynx. We investigated associations and interactions among two kinds of environmental risk factors: i) airborne pathogens, namely closed bedroom window and shared bedroom and ii) pollutants, namely traffic pollution and environmental tobacco smoke (ETS). We evaluated breastfeeding's (BF) protective value against childhood pneumonia. The database consists of responses to a questionnaire in a cross-sectional study. Crude and adjusted Odds Ratios were assessed independently for each risk factor. Combinations of the studied risk factors were analyzed using multivariate logistic regression. Risk factors were evaluated for interactions on the additive scale using the metrics Relative Excess Risk due to Interaction (RERI), Attributable Proportion (AP) and Synergy Index (S). All independent risk factors were significant for children's pneumonia. We also found evidence of possible synergistic interaction between pairs of risk factors that was stronger when one of the risk factors was a closed bedroom window. Remarkably, window opening was associated with reduced risk of pneumonia for children living near heavy traffic pollution. Longer duration BF was more protective than shorter, and exclusive BF was more protective than partial BF against childhood pneumonia. In conclusion, low ventilation (closed bedroom windows), shared bedroom, ETS, and traffic exposure were associated with increased risk of pneumonia. Exclusive BF for more than six months had the greatest protective value against pneumonia.

Associations of Indoor Environmental Quality Parameters with Students' Perceptions in Undergraduate Dormitories: A Field Study in Beijing during a Transition Season

A healthy and comfortable dormitory environment is crucial to the quality of students' daily lives. In this field study, the indoor environmental quality (IEQ) parameters of undergraduate dormitories in Beijing were measured, while questionnaire surveys were conducted to evaluate the corresponding subjective perceptions of students. Integrated environmental monitoring kits were used to collect temperature, relative humidity, CO₂, PM_2.5, PM₁₀, TVOC, formaldehyde, and noise data in the investigated dormitories, during the transition season from winter to spring. Questionnaires and scales were distributed to obtain the students' subjective perceptions of and satisfaction with the IEQ, and their health and well-being status. The measured IEQ data showed that the thermal environment tended to be warm and dry during the heating period. The CO₂ concentrations seriously exceeded standard levels due to insufficient indoor natural ventilation. Noise exposure could sometimes interfere with students' rest. The students' overall satisfaction with the dormitory environment was low, especially in terms of air quality and acoustic environment. The unsatisfactory IEQ factors have led to several health symptoms, poor sleep quality, and slightly lower well-being. Correlations were found between the IEQ parameters and the corresponding subjective perceptions and satisfaction levels. It was speculated that students' satisfaction and well-being could be effectively improved by appropriately adjusting the corresponding IEQ parameters.