| Abstrakt: |
Drug resistance and the distribution of R factors in Salmonellastrains were surveyed using 1,980 strains isolated in Japan from 1955 to 1973. Resistances were mostly restricted to sulfanilamide (SA), tetracycline (TC), and streptomycin (SM), and combinations thereof. The demonstrated frequency of strains resistant to chloramphenicol (CM) was very low as compared with that in Escherichia coliand Shigellastrains. In relation to resistance to TC, CM, SM and SA, the frequency of isolation of single resistance was the highest, followed by triple, double, and quadruple resistance in that order. Low frequency of isolation of quadruple resistance was due to the low frequency of CM resistance in Salmonellastrains and differed from the E. colior Shigellagroup. R factors with single TC resistance was most common, followed by those with TC,SM,SA; SM,SA; TC,CM,SM,SA; and single (SM and SA) resistance, in that order. Kanamycin and ampicillin resistance was unusual and mostly transmissible. |
