OBJECTIVE To investigate and analyze the bacteria on the nurse mask in ICU ward and its air effects disinfection.METHODS Sixty masks were examined for the bacteria numbers,germiculture and drug resistance.The bacteria numbers on the mask were recorded in 2,4,6 and 8 h with or without air disinfection,and the numbers of air bacteria were also estimated before and after air disinfection 2,4,6 and 8 h.The kinds and drug resistance of bacteria in the sputum of patients were recorded during the examining time.RESULTS The meticillin-resistant Staphylococcus(MRS,90.6%) and the Escherichia coli(ECO,9.4%) were the major bacteria on the mask.The numbers of bacteria on the mask at 2,4,6 and 8 h with air disinfection were 1.2?1.5,3.4 ?2.8,4.2?3.4 and 5.3?3.6 CFU/cm2,respectively.The numbers of bacteria on the air before air disinfection were 1264?314 CFU/m3 and after air disinfection 2,4,6 and 8 h were 917?213,790?176,676?179 and 483?167 CFU/m3,respectively.The numbers of bacteria on the mask and on the ward air were decreased obviously after the air disinfection comparing without disinfection.MRS was found in 26.7% patients sputum,and had the same drug-resistance spectrum as the bacteria on the mask.CONCLUSIONS MRS and ECO may be infected through air,and the effective air disinfection could reduce the numbers of bacteria on the air,and decrease the possibility of intercross infection.