Fostering Collaboration Between Infection Prevention and Environmental Services

Let’s take a look at what some studies indicate in terms of the contribution the environment makes to disease transmission. Crnich et al. (2005) point out that “Exogenous colonization originates from a very wide variety of animate and inanimate sources in the intensive care unit environment.” The researchers looked at the causes of ventilator-associated pneumonia (VAP) and noted that a substantial proportion of episodes of VAP are of exogenous origin and caused by healthcare-associated organisms that are not part of the normal oropharyngeal flora, such as Pseudomonas aeruginosa, other multi-resistant Gram-negative bacilli, and Staphylococcus aureus, especially methicillin-resistant strains.

They also looked to environmental sources of colonization in the animate and inanimate environments, with the contaminated hands of HCWs as a leading vector. Crnich et al. (2005) report, “Larson found that 21 percent of hospital employees’ hands were persistently colonized by Gram-negative bacilli, including Acinetobacter, Klebsiella, and Enterobacter, and Goldmann et al. found that as many as 75 percent of neonatal ICU HCWs’ hands were colonized by potentially pathogenic Gram-negative bacilli. Maki found that the hands of 64 percent of ICU personnel sampled at random were colonized at some time by S. aureus, and 100 percent showed transient carriage of a variety of Gram-negative bacilli at least once during the period of surveillance.”

Hota (2004) notes, “Despite documentation that the inanimate hospital environment (e.g., surfaces and medical equipment) becomes contaminated with nosocomial pathogens, the data that suggest that contaminated fomites lead to nosocomial infections do so indirectly. Pathogens for which there is more-compelling evidence of survival in environmental reservoirs include Clostridium difficile, vancomycin-resistant enterococci, and methicillin-resistant Staphylococcus aureus, and pathogens for which there is evidence of probable survival in environmental reservoirs include norovirus, influenza virus, severe acute respiratory syndrome-associated coronavirus, and Candida species. Strategies to reduce the rates of nosocomial infection with these pathogens should conform to established guidelines, with an emphasis on thorough environmental cleaning and use of Environmental Protection Agency-approved detergent-disinfectants.”