title: Surveillance of hepatitis A and E viruses contamination in shellfish in Thailand.
abstract: OBJECTIVE
  To survey for hepatitis A virus (HAV) and hepatitis E virus (HEV) contamination in edible bivalve shellfish.
  
  
  RESULTS
  A total of 213 shellfish (52 oysters, 69 cockles and 92 mussels) collected from a culture farm and two retailed markets were investigated for HAV and HEV contamination by reverse transcription-polymerase chain reaction (RT-PCR) assay using HA2-HA1 (capsid region) and HE366-HE363 (ORF2/3 overlapping region) primers, respectively. It was found that 3.8% of the shellfish and 2.9 and 6.5% of the cockle and mussel, respectively, showed positive for HAV detection. Nucleotide sequencing of all the 8 HAV-positive shellfish revealed 97-100% similarity to HAV subgenotype IA. Interestingly, viruses were found more frequently in the gills than in digestive tissue (4.5%vs 0.5%, P = 0.045). All the shellfish were negative for HEV.
  
  
  CONCLUSIONS
  Significant contamination of HAV in edible bivalve shellfish was observed. Beside digestive tissue, gills are one of the important samples for viral genome detection.
  
  
  CONCLUSIONS
  HAV-contaminated shellfish can play a role as reservoirs and/or vehicles in faecal-oral transmission in Thailand, and further monitoring of such a contamination is required.
authors.affiliation: Department of Microbiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: A
authors.initials: A
authors.lastname: Namsai
authors.forename: S
authors.initials: S
authors.lastname: Louisirirotchanakul
authors.forename: N
authors.initials: N
authors.lastname: Wongchinda
authors.forename: U
authors.initials: U
authors.lastname: Siripanyaphinyo
authors.forename: P
authors.initials: P
authors.lastname: Virulhakul
authors.forename: P
authors.initials: P
authors.lastname: Puthavathana
authors.forename: K S
authors.initials: KS
authors.lastname: Myint
authors.forename: M
authors.initials: M
authors.lastname: Gannarong
authors.forename: R
authors.initials: R
authors.lastname: Ittapong
mesh_terms: D000818:Animals; D049872:Bivalvia / Q000821:virology; D049873:Cardiidae / Q000821:virology; D005506:Food Contamination; D006506:Hepatitis A / Q000635:transmission* / Q000821:virology; D030041:Hepatitis A virus / Q000235:genetics / Q000302:isolation & purification*; D016751:Hepatitis E / Q000635:transmission* / Q000821:virology; D016752:Hepatitis E virus / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D010125:Ostreidae / Q000821:virology; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012758:Shellfish / Q000821:virology*; D013785:Thailand