Seasonal variation of entertoxigenic Escherichia coli among children with diarrhoea in Bangkok.

ETEC which produced both LT and ST or LT alone were isolated from 7.4 percent (18/244) of children with diarrhoea treated at two hospitals in Bangkok, Thailand between May 1, 1980 and April 30, 1981. These enteric pathogens were only isolated from children with diarrhoea during the dry and the beginning of the wet season. Eighty-three percent (15/18) children infected with ETEC were infected with antibiotic resistant isolates. One hundred percent of LT + ST + E. coli and 76 percent (50/66) of LT + ST - E. coli were resistant to two or more antibiotics. Fourteen of 15 (93%) ETEC transferred antibiotic resistance and nine of 14 (64%) isolates which transferred resistance in bacterial conjugation experiments also transferred toxigenicity. This experience suggests that the widespread use of antibiotics in Thailand could increase the prevalence of antibiotic resistant enterotoxigenic bacteria.