Determination of several potential virulence factors in Vibrio spp. isolated from sea water Original Research Article

Fifty-two Vibrio strains isolated from sea water (20 Vibrio alginolyticus, 10Vibrio parahaemolyticus , 5 Vibrio cholerae non-01, 5 Vibrio vulnificus, 5 Vibrio fluvialis, 5Vibrio furnissii and 2 Vibrio metshnikovii) were assayed for enzymatic (urease, lipase, gelatinase, and haemolysin) and biological (adhesiveness, cytotoxicity and enterotoxicity) activities and enteropathogenicity in white mice. Lipase and gelatinase activities were observed in 100% of the strains, while haemolytic activity was found in only 7·2% and urease activity was detected in 19·2% of the strains. Adhesiveness and cytotoxicity were observed in 63% and 57·6%, respectively, of the strains. Twenty-three percent of the strains gave positive results in the ileal loop test in rats and 23% showed the ability to infect the laboratory animals. Positivity in vivo was accompanied by the presence of more than one marker of virulence. It appears that some of these halophilicVibrio spp. are potentially pathogenic, and that their pathogenicity could be the result of a combination of factors.