title: Detection of both hepatitis A virus and Norwalk-like virus in imported clams associated with food-borne illness.
abstract: Hepatitis A virus (HAV) and Norwalk-like virus (NLV) were detected by reverse transcription-PCR in clams imported into the United States from China. An epidemiological investigation showed that these clams were associated with five cases of Norwalk-like gastroenteritis in New York State in August 2000 (Food and Drug Administration Import Alert 16-50). They were labeled "cooked" but appeared raw. Viral RNA extraction was performed by using dissected digestive tissues rather than whole shellfish meats; this was followed by glycine buffer elution, polyethylene glycol precipitation, Tri-Reagent treatment, and purification of poly(A) RNA with magnetic beads coupled to poly(dT) oligonucleotides. We identified HAV and NLV as genotype I and genogroup II strains, respectively. Both viruses have high levels of homology to Asian strains. An analysis of fecal coliforms revealed a most-probable number of 93,000/100 g of clam meat, which is approximately 300-fold higher than the hygienic standard for shellfish meats.
authors.affiliation: U.S. Department of Agriculture, Agricultural Research Service, Microbial Food Safety Research Unit, Delaware State University, Dover, Delaware 19901, USA. dkingsle@dsc.edu
authors.forename: David H
authors.initials: DH
authors.lastname: Kingsley
authors.forename: Gloria K
authors.initials: GK
authors.lastname: Meade
authors.forename: Gary P
authors.initials: GP
authors.lastname: Richards
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D049872:Bivalvia / Q000821:virology*; D017250:Caliciviridae Infections / Q000821:virology; D003132:Commerce; D004196:Disease Outbreaks; D005516:Food Microbiology; D005759:Gastroenteritis / Q000821:virology*; D006506:Hepatitis A / Q000821:virology; D030041:Hepatitis A virus / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008969:Molecular Sequence Data; D029322:Norovirus / Q000235:genetics / Q000302:isolation & purification*; D012367:RNA, Viral / Q000032:analysis; D020133:Reverse Transcriptase Polymerase Chain Reaction; D017422:Sequence Analysis, DNA
chemical_list: D012367:RNA, Viral