Susceptibilities of bacteria to different antibiotic regimens. Study in two nursery populations.

Hospital nursery A has used chloramphenicol and nursery B has used the combination of penicillin G sodium and kanamycin sulfate routinely in the treatment of neonatal sepsis and other bacterial infections. A hypothesis was formulated that these different antibiotic pressures would select out a substantial number of populations of resistant bacteria in each of the two nurseries. This was tested by periodic sampling of the skin, mouth, and rectal flora of babies and the permanent personnel in these nurseries. These bacteria were studied for susceptibility to a number of antibiotics. The population of resistant strains selected out was correlated with the antibiotics used in each nursery. There is a need for continuing surveillance of hospital nursery strains of bacteria for in vitro susceptibilities to commonly prescribed antimicrobials.