[Article on SEIMC Procedure No.42: Environmental microbiological monitoring].

The inanimate hospital environment is rarely implicated in infection transmission, except among vulnerable patients. Some authors argue against the use of environmental surveillance cultures because the tests can be expensive and time consuming, and because they should not be used instead of quality control and good practices in disinfection and maintenance procedures. Routine environmental sampling is not usually advised, except in situations where sampling is directed by epidemiologic principles, and results can be applied to adopt infection control measures. The incidence of health-care associated infections can be minimised by appropriate maintenance of medical equipment such as endoscope cleaning and disinfection, adherence to water-quality standards for haemodialysis, and to ventilation standards for specialised care environments such as isolation units, or operating rooms. This paper reviews the current knowledge on surveillance cultures in these settings in order to prevent iatrogenic infections in operating and isolation rooms, haemodialysis and endoscope reprocessing units, and cultures related to nosocomial infection outbreaks.