Antibiotic Resistance and R Factors in Gram-Negative Bacteria Isolated in a Hospital for Infectious Diseases: IV. Influence of Hospital Environment on the Incidence and Type of Resistance in Enteric Bacteria

Abstract

Patients in two wards at Roslagstull Hospital were studied in order to evaluate the influence of hospital environment on the incidence and type of resistance in gram-negative bacteria. Antibiotic treatment was not used in these wards during the period of study. In an open ward with short-term patients it was found that R factors were circulating among the patients. From admission to discharge 2–3 weeks later the incidence of resistant Escherichia coli strains did not increase, but predominance of such strains increased from 20% on admission to 45% at discharge. 11 patients, who had sensitive E. coli on admission, picked up R factors during their stay. In a ward with patients nursed for very long periods the proportion of resistant gram-negative strains was extremely high (88%). R factors seemed to have spread among strains of different species recovered from different sites of the same individual.