The dominance of pandemic serovars of Vibrio parahaemolyticus in expatriates and sporadic cases of diarrhoea in Thailand, and a new emergent serovar (O3 : K46) with pandemic traits.
Vibrio parahaemolyticus is a major cause of gastroenteritis worldwide. A total of 95 V. parahaemolyticus isolates belonging to 23 different serovars were identified in a case-control study of expatriates and Thai adults from 2001 to 2002 in Thailand. Fifty-two per cent of isolates (49/95) were resistant to ampicillin and sulfisoxazole, but all isolates were susceptible to ciprofloxacin and trimethoprim-sulfamethoxazole, two antibiotics commonly used to treat traveller's diarrhoea. All isolates were positive for the species-specific toxR gene, and 91 and 5 were positive for the thermostable direct haemolysin (tdh) gene and the tdh-related (trh) gene, respectively. Sixty-five isolates were assigned to the pandemic group of V. parahaemolyticus by a group-specific PCR and the presence of the orf8 gene. The pandemic isolates belonged to three recognized serovars (O3 : K6, O1 : K25, O1 : KUT) and a new serovar, O3 : K46. This new serovar harboured pandemic traits. PFGE analysis revealed that all pandemic isolates including serovar O3 : K46 were closely related and clearly distinct from the non-pandemic isolates. In summary, three well-known serovars of pandemic V. parahaemolyticus isolates were identified as a major cause of diarrhoea in Thailand and a new V. parahaemolyticus isolate, serovar O3 : K46, with pandemic traits was detected.
Serichantalergs
Oralak
O
Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
Bhuiyan
Nurul Amin
NA
International Centre for Diarrhoeal Disease Research (ICDDR,B), Dhaka 1212, Bangladesh.
Nair
Gopinath Balakrish
GB
International Centre for Diarrhoeal Disease Research (ICDDR,B), Dhaka 1212, Bangladesh.
Chivaratanond
Orapan
O
Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
Srijan
Apichai
A
Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
Bodhidatta
Ladaporn
L
Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
Anuras
Sinn
S
Bumrungrad Hospital, Bangkok 10110, Thailand.
Mason
Carl J
CJ
Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
D000328:Adult; D000900:Anti-Bacterial Agents / Q000494:pharmacology; D000942:Antigens, Bacterial / Q000032:analysis; D000954:Antigens, Surface / Q000032:analysis; D001426:Bacterial Proteins / Q000235:genetics; D016172:DNA Fingerprinting; D004269:DNA, Bacterial / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics; D003967:Diarrhea / Q000453:epidemiology / Q000382:microbiology*; D004196:Disease Outbreaks; D016521:Electrophoresis, Gel, Pulsed-Field; D004641:Emigration and Immigration; D006460:Hemolysin Proteins / Q000235:genetics; D006801:Humans; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D019081:O Antigens / Q000032:analysis; D010641:Phenotype; D016133:Polymerase Chain Reaction; D012703:Serotyping; D013785:Thailand / Q000453:epidemiology; D014157:Transcription Factors / Q000235:genetics; D014735:Vibrio Infections / Q000453:epidemiology / Q000382:microbiology*; D014736:Vibrio parahaemolyticus / Q000145:classification* / Q000187:drug effects / Q000235:genetics / Q000302:isolation & purification*
D000900:Anti-Bacterial Agents; D000942:Antigens, Bacterial; D000954:Antigens, Surface; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004268:DNA-Binding Proteins; D006460:Hemolysin Proteins; C030659:K antigens; D019081:O Antigens; D014157:Transcription Factors; C088609:thermostable direct hemolysin-related hemolysin protein, Vibrio parahaemolyticus; C066719:toxR protein, bacteria