[Inc J plasmids identified for the first time in Vibrio cholerae El Tor].

Two epidemic outbreaks of cholera occurred in eastern Algeria in 1994. Sixteen strains of Vibrio cholerae El Tor were isolated from stools and contaminated water. Studies to determine antibiotic sensitivity documented multiresistance in these strains. Minimal inhibiting concentrations ranged from 6 to 32 micrograms/ml for chloramphenicol, from 8 to 24 micrograms/ml for tetracycline except minocycline, and from 15 to 32 micrograms/ml for furanes. Higher values were found for other antibiotics such as trimethoprime (1,500 micrograms/ml), streptomycine (128 micrograms/ml) and sulfamides (128 micrograms/ml). High-grade resistance of Vibrio cholerae El Tor to streptomycine and trimethoprime in association with resistance to 0:129 suggests that transposon is the underlying genetic factor. All resistance markers were located on a single structure that can be transferred to a Escherichia coli receptor and belongs to an Inc J incompatibility group. The fact that plasmid DNA could not be visualized on agarose gel after extraction is also evidence for a transferable transposon.