Enumeration of Vibrio Species, Including V. Cholerae , from Samples of an Oyster Growing Area, Grays Harbor, Washington

Water, shellfish, and sediment samples from Grays Harbor, a major commercial oyster producing estuary in the State of Washington, were examined for levels of Vibrio species. Non-01 V. cholerae was found at low levels in 37.8% of the samples. While V. parahaemolyticus was found in all samples, levels were low. V. mimicus and V. fluvialis were found infrequently and at low levels. Potentially pathogenic strains of non-01 V. cholerae and Kanagawa positive V. parahaemolyticus were isolated from oysters suggesting a potential for human illness.