Vibrio parahaemolyticus infectious for both humans and edible mollusk abalone

Abstract

The aims of this study are to report evidence of the first laboratory-acquired infection of Vibrio parahaemolyticus associated with handling experimentally infected abalones and to describe the virulence of the two bacterial strains tested in these animals. Two strains of V. parahaemolyticus, one from the stool of a patient with acute gastroenteritis (strain 880713) and the other from the hemolymph of a diseased small abalone Haliotis diversicolor supertexta (strain 880915), were identified and characterized. Both strains were lethal to small abalone, with similar LD 50 values (8.36–8.41 × 10 4 colony-forming units/g abalone). Laboratory-acquired infection resulted in one individual experiencing two episodes of acute gastroenteritis due to handling virulence tests during a 1-week interval. Our present results suggest that a V. parahaemolyticus strain isolated from the stool of a patient with gastroenteritis was infectious for small abalone, a major species of edible mollusk abalone cultured in Taiwan, while a similar strain isolated from hemolymph of a diseased small abalone was infectious for humans. This is the first report of V. parahaemolyticus virulent to small abalone as a zoonotic pathogen.