Enterotoxigenic Escherichia coli in Central Australia: diagnosis using cloned and synthetic nucleic acid probes.

Feces from 169 children admitted with diarrhea to Alice Springs Hospital, were screened for enterotoxigenic E. coli (ETEC) using specific DNA probes. E. coli which hybridized with probes for ST-P, ST-H and LT were confirmed by bioassay for toxin production. Fifty children were shown to excrete ETEC. The probes for LT correlated well with bioassay; however, probes for ST-H and ST-P hybridized with more E. coli than were shown to produce toxin by bioassay. When probing for ST was repeated using a synthetic oligonucleotide probe, only those specimens which were bioassay-positive hybridized with the probe.