Objective: The aim of our study was to determine what a hazard for patients creates the presence of cockroaches in hospital environment.
Material and methods: The probable hospital infections cases in 9 hospitals in Warsaw were found in database of the Country Hospital Morbidity Register for the year 2004 and correlation between such factors as: drug resistance of bacteria isolated from external part of cockroach's bodies, their ability to biofilm building, adherence, resistance to disinfectants, resistance of cockroaches to insecticides, infestation level vs. infections of several body systems was examined.
Results: The microbiological hazard of cockroaches in hospital environment has been proven by our findings that some of bacterial strains carried on the body of cockroaches belonged to well known species responsible for hospital infections everywhere The strains resistant to several antibiotics used in hospital and the strains able to form virulence factors were found. Some correlation was found between resistance of cockroaches for biocides and higher infestation of the hospital environment.
Conclusions: Cockroaches infected in hospital environment might be the active carrier of bacterial strains as well as indicator of the bacterial presence on the surfaces in the hospital building not enough treated with disinfectants. On the base of our findings we may suppose that in hospital infections the role of infected cockroaches are less important than the other factors but should be not completely neglected. Surveillance and control of hospital infections should be more completed, connected not only with continuous monitoring of resistance of bacterial strains to antibiotics but also to disinfectants used in hospital as well as evaluation of infestation of the hospital environment and resistance of cockroaches to biocides.