Disinfection of Acinetobacter baumannii-contaminated surfaces relevant to medical treatment facilities with ultraviolet C light.

The efficacy of ultraviolet C (UVC) light (100-280 nm) in the decontamination of three hospital-related surfaces, namely, unpainted/painted aluminum (bed railings), stainless steel (operating tables), and scrubs (laboratory coats), was investigated. Acinetobacter baumannii cells were inoculated (10(5) or 10(3) cells) on small coupons and dried overnight in a class II biosafety cabinet. Drying resulted in < or =50% loss of viability. The UVC fluence of 90 J/m2 was observed to be very effective in the decontamination of cells from all metal coupon surfaces (complete killing). However, the same fluence was ineffective in the decontamination of scrubs. The effectiveness of two other common disinfection practices, that is, 15 minutes of boiling or spraying with 70% ethanol, was investigated for the scrubs. Although ethanol treatment was ineffective, the boiling treatment was very effective (complete killing). These results establish that metal surfaces can be decontaminated with UVC irradiation and boiling treatment is effective for scrub decontamination.