In-vitro activity of DR-3355, an optically active isomer of ofloxacin, against bacterial pathogens associated with travellers' diarrhoea.

The in-vitro activity of DR-3355, the S-(-)-isomer of ofloxacin, was determined against bacterial pathogens associated with travellers' diarrhoea. DR-3355 was highly active against isolates of enteropathogenic Escherichia coli (MIC90 0.05 mg/l), Salmonella spp. (MIC90 0.10 mg/l), Shigella spp. (MIC90 0.10 mg/l), Campylobacter jejuni (MIC90 0.39 mg/l) and Vibrio parahaemolyticus (MIC90 0.39 mg/l). The activity of DR-3355 against these bacteria was generally two- to eight-fold greater than that of ofloxacin and equal to, or only two-fold less than, that of ciprofloxacin with the exception of isolates of C. jejuni, which were two-fold less susceptible to ciprofloxacin than to DR-3355.