Chloramphenicol resistant Salmonella species isolated between 1978 and 1987

During the ten year study i.e. 1978 to 1987, out of 53,251 cases of suspected enteric fever, S.typhi was isolated from 4005 cases (7%) and S.para typhi 'A' from 1108 cases (2.5%). A total of 52 strains of S. typhi and 4 strains of S.para typhi 'A' were found to be resistant to chloramphenicol. Minimal inhibitory concentration was greater than 256 micrograms/ml of all the strains of S.typhi and S.para typhi 'A'.