Abstract: ［Abstract］Objective〖HTSS〗To investigate the relevance between the multidrug-resistant Acinetobacter baumannii(MDR-AB） hospital acquired pneumonia and environmental pollution in intensive care unit(ICU). Based on the result, we can provide environmental and epidemiological basis for preventing and controlling MDR-AB nosocomial infection in ICU patients.
〖HTH〗〖WTHZ〗Methods〖HTSS〗With field epidemiological investigation method, we carried out large area hygiene sampling monitoring on three MDR-AB hospital acquired pneumonia patients,environment and medical staff in ICU before and after the intervention. Using VITEK-2 Compact bacteria identification and drug susceptibility analysis system we identified the specific strain of bacteria and corresponding drug susceptibility. Zone and color separation method was adopted in the environmental sterilization and the effect of intervention was traced.
〖HTH〗〖WTHZ〗Results〖HTSS〗Before the intervention we monitored 80 environmental samples. MDR-AB strains of consistent drug-resistant patterns with previous MDR-AB strains isolated from patients′ sputum cultures were found in 14 samples, including computer keyboards at the nursing station, hands of medical staff, bed sheets, lids of hand disinfection solution, scissors in rescue vehicles, air-returning outlets, patients chest skin, cuffs of isolation clothes and bed baffle handrails. No MDR-AB was found in 146 environmental samples after the intervention in the following two months. Six months after the intervention. The qualified rate of specimens increased from 77.50% to 96.57%, and the hospital infection rate decreased from 2.15%(214/9 965) to 1.56%(185/11 866). Which was of significant difference from the rate before the intervention（P＜0.05）. 
〖HTH〗〖WTHZ〗Conclusion〖HTSS〗The occurrence of MDR-AB hospital infection is highly related to the environmental pollution. Intervention with sterilization based on zone and color separation can effectively lower the risk of hospital infection outbreak.

Key words: multidrug-resistant Acinetobacter baumannii, intensive care unit, cross infection