OBJECTIVETo study the effects of weather conditions and occupational hygiene on SARS outbreak.

METHOD(1) Meteorological parameters around SARS outbreaks in 2003 in 9 cities (Guangzhou, Beijing, Tianjin, Taiyuan, Hong Kong, Taipei, Singapore, Toronto and Hanoi) were analyzed; (2) Causes of hospital infection were also analyzed from an occupational hygiene point of view.

RESULTS(1) The amplitude of air temperature, air pressure and diurnal temperature difference were greater around SARS outbreaks in most of the cities. Higher airborne particles concentration and lower wind speed were measured prior to SARS outbreaks in the cities with the most serious epidemic situation. The ten-day mean value of air temperature before SARS outbreaks in 9 cities was 16.6 degrees C +/- 7.6 degrees C, suggesting that coronary virus infection, which has been considered to cause SARS by now, may be most active at 9 degrees C - 24 degrees C. (2) Occupational hygiene in hospital proved to be an important socio-behavior factor for SARS outbreak. All hospital infection could be attributed to defects in the key links of occupational hygiene.

CONCLUSIONSGreater fluctuations of air temperature and higher airborne particles concentration in winter and spring, as well as poor occupational hygiene conditions are significant promoters of SARS outbreak. Warning of atmospheric conditions favorable to SARS, and improvement in occupational hygiene management is the key to prevention from SARS outbreak.