Chloramphenicol resistance of Salmonella species in India, 1959-61.

Salmonella infections are quite frequent in India and are generally treated with chloramphenicol. In pursuance of a proposal of the WHO Expert Committee on Antibiotics, a survey has been made of the resistance to this antibiotic of 867 Salmonella strains isolated in India over the period 1959-61. It was found that most of the 24 serotypes studied were sensitive to 4-8 mug of chloramphenicol per ml of agar medium, although rather higher concentrations were required to kill some strains of Salm. paratyphi A and, particularly, of Salm. typhi. Analysis of the findings on Salm. typhi also indicate that its degree of resistance to chloramphenicol has increased over the years 1959-61.