TWENTY-FOURTH ANNUAL EASTERN FISH HEALTH WORKSHOP Royal Pavilion Resort, Atlantic Beach, NC MARCH 9-11, 1999 Isolation Of Vibrio cholerae Non 01 From Sick, Wild White Perch Collected From Chesapeake Bay Tributaries Ana M. Baya1, Tong Li2, Valerie Louis3, Eric May4, Charles Poukish5, Larry Pieper4, Craig Weedon4, Cindy Driscoll4 and Jimmy C.Huang2, Brenda Kibler4, Brett Coakley4, Susan Knowles4 University of Maryland1, Maryland Department of Agriculture2, Center for Marine Biotechnology3, Maryland Department of Natural Resources4, Maryland Department of the Environment5 Vibrio cholerae non-01 is a well-recognized pathogen and has a wide distribution in bays and estuaries and in shellfish where it can exist either free-living or as a zooplankton-associated organism. It can be highly virulent,e.g. eels can be infected by immersion challenge (at 21-26C) with as few as 1.26x102 cells/ml. Vibrio cholerae non-01 was isolated in pure culture from the internal organs of 40 white perch collected from two different rivers where approximately twenty percent were exibiting petechiae or some type of skin reddening around the jaws and fins, and some fins were eroded. After biochemical identification (API 20E 1347024) this isolate was confirmed as Vibrio cholerae by molecular methods. PCR assays were positive for a probe specific to V. cholerae species and for a probe against the tox-R gene that regulates V. cholerae virulence factors. Direct fluorescence antibody assay (DFA) using monoclonal antibodies specific for the 01 and 0139 lipopolysaccharide antigen in the outer membrane of V.cholerae showed that the V.cholerae strain was non 01 and non 0139. These results suggest that the strain isolated was non epidemic V. cholerae Tissues from eight white perch were examined histopathologically. All 8 fish examined had a chronic splenitis manifested as multifocal mononuclear cell aggregates and ellipsoid hypertrophy. In four of the individuals, there was sclerosis of the glomeruli with thickening of the visceral capsule and occasional wire looping. Three exhibited a multifocal chronic active pericholangitis with neutrophils and mononuclear cell infiltrates present in peribilliary zones. Skin lesions were present but were primarily erosive with no indication that they began as a consequence of the bacteremia. Controlled transmission studies are planned in white perch and other species to determine the virulence range of the V.cholerae isolate. Return to 24th Annual Eastern Fish Health Workshop Return to Leetown Science Center Home Page