Prevalence of pandemic thermostable direct hemolysin-producing Vibrio parahaemolyticus O3:K6 in seafood and the coastal environment in Japan.
Although thermostable direct hemolysin (TDH)-producing Vibrio parahaemolyticus has caused many infections in Asian countries, the United States, and other countries, it has been difficult to detect the same pathogen in seafoods and other environmental samples. In this study, we detected and enumerated tdh gene-positive V. parahaemolyticus in Japanese seafoods with a tdh-specific PCR method, a chromogenic agar medium, and a most-probable-number method. The tdh gene was detected in 33 of 329 seafood samples (10.0%). The number of tdh-positive V. parahaemolyticus ranged from <3 to 93/10 g. The incidence of tdh-positive V. parahaemolyticus tended to be high in samples contaminated with relatively high levels of total V. parahaemolyticus. TDH-producing strains of V. parahaemolyticus were isolated from 11 of 33 tdh-positive samples (short-necked clam, hen clam, and rock oyster). TDH-producing strains of V. parahaemolyticus were also isolated from the sediments of rivers near the coast in Japan. Representative strains of the seafood and sediment isolates were examined for the O:K serovar and by the PCR method specific to the pandemic clone and arbitrarily primed PCR and pulsed-field gel electrophoresis techniques. The results indicated that most O3:K6 tdh-positive strains belonged to the pandemic O3:K6 clone and suggested that serovariation took place in the Japanese environment.
Hara-Kudo
Yukiko
Y
Department of Biomedical Food Research, National Institute of Infectious Diseases, Shinjuku-ku, Tokyo 162-8640, Japan.
Sugiyama
Kanji
K
Nishibuchi
Mitsuaki
M
Chowdhury
Ashrafuzzaman
A
Yatsuyanagi
Jun
J
Ohtomo
Yoshimitsu
Y
Saito
Akinobu
A
Nagano
Hidetoshi
H
Nishina
Tokuhiro
T
Nakagawa
Hiroshi
H
Konuma
Hirotaka
H
Miyahara
Michiko
M
Kumagai
Susumu
S
D000818:Animals; D001427:Bacterial Toxins; D015169:Colony Count, Microbial; D016521:Electrophoresis, Gel, Pulsed-Field; D005399:Fishes / Q000382:microbiology; D005618:Fresh Water / Q000382:microbiology*; D006460:Hemolysin Proteins / Q000235:genetics / Q000378:metabolism*; D006801:Humans; D007564:Japan / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D015995:Prevalence; D017747:Seafood / Q000382:microbiology*; D012758:Shellfish / Q000382:microbiology; D014735:Vibrio Infections / Q000453:epidemiology* / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000145:classification* / Q000235:genetics / Q000302:isolation & purification
D001427:Bacterial Toxins; D006460:Hemolysin Proteins; C068489:thermostable direct hemolysin