ABSTRACT
I. BACKGROUND Vibrio parahaemolyticus is a halophilic marine bacterium first isolated from Shirasu, semi-dried juvenile sardine, implicated in an outbreak of food poisoning in Japan in 1950. It was soon shown that gastroenteritis due to this organism accounted for nearly half of bacterial food poisoning cases in Japan where raw seafood is consumed very often and that this organism is abundant in the seawater environment around Japan in summer. The first food poisoning case due to V. parahaemolyticus reported outside Japan was from the East Coast of the United States in 1971. Distribution of this organism in the marine environment of the Pacific Northwest was then studied. Clinical cases and distribution of V. parahaemolyticus in other parts of the world have been reported since then. V. parahaemolyticus has thus been recognized as an important seafoodborne pathogen worldwide (1). Raw or undercooked seafood contaminated with this organism is the main source of infection. Nowadays, various seafoods are transported across the international borders, and such seafood can be contaminated by V. parahaemolyticus at considerable levels although the concentration of virulent strains is supposed to be very low. International travelers also often suffer from V. parahaemolyticus infection. Very recently, the use of molecular genetic tools allowed the investigation of the epidemiology of V. parahaemolyticus infection on a global scale.
