Development of a 5-minute rapid test for detecting Vibrio cholerae O139

Vibrio cholerae O139 is an etiology of cholera in Thailand. We determined to prepare a rapid test to detect V cholerae O139 using an immunochromatographic method to be used for surveillance and use in community laboratories. We conjugated murine monoclonal antibodies specific to the lipopolysaccharide of V. cholerae O139 with colloidal gold particles. The sensitivity of the test was determined using 10-fold dilutions of V. cholerae O139. The lowest number of bacterial cells detected by the test was 10(6) cfu/ml. The specificity was determined using 51 isolates of pure cultures, including V. cholerae serogroups O1, O139, and non-O1/non-O139 and other enteric bacteria; 27 rectal swab specimens and 100 specimens of enriched alkaline peptone water, 50 of which contained V. cholerae O1 and the other did not contain V. cholerae O1. The rapid test showed specificity to V cholerae O139 and no cross reaction with V cholerae O1, V. cholerae non-O1/ non-O139, and other enteric bacteria. The test is rapid, simple and easy to use.