[Use of markers of hospital strains in studying the occurrence of nosocomial infections].

The submitted paper deals with one of the possible aspects of the investigation of nosocomial infections, i.e. investigations of the properties of hospital strains, their importance and possible use. The incidence of bacterial hospital strains was investigated in a surgical department of a district hospital of the North Bohemian region in October 1990; at the time of the survey 29 nosocomial infections (36.1%) were revealed by the prevalence method. Bacterial hospital strains were isolated from patients with a nosocomial infection, from the attending staff and the hospital environment. The following markers were investigated: biotyping, phagotyping, serotyping, toxin production, sensitivity to antimicrobial substances and sensitivity to disinfectants. Based on results of marking of hospital strains 7 incidences with a possible epidemiological association were detected where the hospital strain of equal or very similar properties dominated. The results of the investigation confirmed the important participation of the attending staff in the spread of nosocomial infections, in particular via contaminated hands, and drew attention to shortcomings as regards adherence to the hygienic and epidemiological regime in the investigated department.