Isolated from sea water and shrimp farms Methods: To detect the toxin genes, the polymerase chain reaction (PCR) method was used to verify the toxin genes included bceT, cytK, the hemolysin genes (hblA, hblB, hblC, hblD) and the non-hemolytic genes (nheA, nheB, nheC) as well as the emetic gene ces.