The Role of the Surface Environment in Healthcare-Associated Infections

David J. Weber; Deverick Anderson; William A. Rutala


Curr Opin Infect Dis. 2013;26(4):338-344. 

In This Article

Contamination of Surfaces in the Hospital Environment

The survival of nosocomial pathogens on environmental surfaces has been reviewed.[9,10] MRSA, VRE, Pseudomonas spp., Acinetobacter spp., and norovirus are capable of surviving for days to weeks on dry inanimate surfaces. C. difficile spores may survive on environmental surfaces for months.

Multiple studies have demonstrated that surfaces in the rooms of patients colonized or infected with important healthcare-associated pathogens are frequently contaminated. The proportion of hospital surfaces contaminated with MRSA has varied in published reports from 1 to 27% of surfaces in patient rooms on regular hospital wards, and from a few percent to 64% of burn units with MRSA patients.[3] One review reported that 7–29% of environmental sites were positive in areas housing VRE patients.[11] More recent studies have reported that the frequency of environmental contamination reached 60–70% in the room of patients colonized with VRE at three or four body sites and that 36–58% of chairs and couches used by VRE patients were positive in areas housing VRE patients.[3] Many studies have demonstrated widespread environmental contamination with C. difficile in the rooms of patients with C. difficile infection (CDI), with a range of 2.9–75%.[4] Finally, the frequency of environmental contamination with Acinetobacter spp. in outbreak settings has been reported by investigators to range from 3 to 50%.[4]

Although hospital room surfaces are frequently contaminated, the level of contamination is generally less than 10 organisms per cm2. For example, Huslage et al.[12] reported that the number of colony forming units (CFU) was less than 100 bacteria per RODAC plate (25 cm2). Importantly, there was no statistical difference in the level of contamination despite whether the surface was a high, medium or low touch surface. Similar findings have been reported by others.[13] Several studies have evaluated the level of microbial contamination of C. difficile on surfaces in the rooms of patients with CDI. Most of these studies reported that surfaces were contaminated with less than 1–2-log10C. difficile, but one study that sampled a larger area using a sponge technique reported 1300 colonies.[7]