Antibiotic resistance and transmissible R-factors in the intestinal coliform flora of healthy adults and children in an urban and a rural community

Faeces of healthy adults and of children under the age of 5, none of whom were attending hospital or receiving antibiotics, were examined for the presence of antibiotic resistant coliform bacilli.A higher proportion of children (67%) than of adults (46%) carried resistant strains and this difference was observed in both the rural and urban groups.Rural members of both age groups more often carried resistant organisms than urban members. Among rural adults, the incidence of drug-resistant strains was 63% in those whose occupation involved close contact with farm animals, compared with 29% in those with other occupations. The survey took place before the implementation of the Swann Report could have influenced the use of antibiotics in animal foodstuffs.Transmissible R-factors were demonstrated in 61% of the resistant strains. The incidence of transmissible resistance was similar among adults and children in town and country.

Method for assessing the frequency of transfer of an R factor on solid media and for isolating cells of the donor type from a predominantly repressed culture

A method for assessing the incidence of R factor transfer on solid media is described. The method gives values similar to those obtained with conventional techniques but allows the derepressed cells from a predominantly repressed population to be isolated.