Table 1.
Associations between common cold and demographic information and living habits of 3436 dormitory occupants, 2006–2007.
Figure 1.
Comparison of common cold incidence and duration for different occupancy levels.
Figure 2.
Associations between crowdedness and common cold annual incidence ≥6 times and duration ≥2 weeks.
Odds ratios were adjusted for gender, age, hours spent indoors, family member allergy history and exposure to environmental tobacco smoke. Circles represent adjusted odds ratio (AOR) for incidence. Dashes represent AOR for duration. 95% confidence interval is demonstrated.
Table 2.
Temperature and relative humidity in rooms with different occupancy levels and outdoor air flow rates, mean (standard deviation).
Figure 3.
Associations between ventilation rate and common cold annual incidence ≥6 times.
1 Proportion of occupants with ≥6 common colds in the previous 12 months. 2 Odds ratios were adjusted for gender, age, family member allergy history, exposure to environmental tobacco smoke, building age and crowdedness. AOR: adjusted odds ratio; CI: confidence interval.
Figure 4.
Associations between common cold infection rates and mean ventilation rate in winter in buildings constructed after year 1993.
1 Proportion of occupants with ≥6 common colds in the previous 12 months.
Table 3.
Comparison of estimated and self-reported basic reproduction number of common cold per day.
Figure 5.
Critical indoor CO2 concentrations above background in dorm room as a function of exposure time and quantum generation rate.
(a) Quantum generation rate = 2 quanta/h, Ca = 37000ppm. (b) t = 56 hours (i.e. 7days), Ca = 37000 ppm.