Characteristics of non-cholera Vibrios isolated from cases of human diarrhoea.

Eighty-two organisms tentatively identified as non-cholera vibrios were isolated from cases of diarrhoea occurring in East Pakistan. In 19 well-studied cases they were the predominant organism recovered, and a rise in agglutinating-antibody titre was found in six of these cases.Because of this additional evidence that non-cholera vibrios cause diarrhoeal disease, it was necessary to evaluate simple screening tests as a means of recognizing them. It was found that all organisms that produced a gelatinase "zone", had typical vibrio morphology on microscopic examination, produced colonies showing a characteristic picture when examined by oblique light microscopy, and gave a positive "string" test were vibrios. Agglutination tests with vibrio O group I antiserum and with antirough vibrio serum distinguished the organisms from Vibrio cholerae. Since these organisms may be discarded by enteric diagnostic procedures directed mainly towards the isolation and identification of Salmonella and Shigella, it is recommended that the screening tests for these organisms be carried out in cases of diarrhoea of unknown etiology.