Kingsley David H, Meade Gloria K, Richards Gary P
U.S. Department of Agriculture, Agricultural Research Service, Microbial Food Safety Research Unit, Delaware State University, Dover, Delaware 19901, USA.
Appl Environ Microbiol. 2002 Aug;68(8):3914-8. doi: 10.1128/AEM.68.8.3914-3918.2002.
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.
通过逆转录聚合酶链反应（RT-PCR）在美国从中国进口的蛤中检测到甲型肝炎病毒（HAV）和诺沃克样病毒（NLV）。一项流行病学调查显示，这些蛤与2000年8月纽约州的5例诺沃克样肠胃炎病例有关（食品药品管理局进口警示16-50）。它们被标记为“已煮熟”，但看起来是生的。病毒RNA提取采用解剖后的消化组织而非整个贝类肉进行；随后进行甘氨酸缓冲液洗脱、聚乙二醇沉淀、Tri-Reagent处理，并用与聚（dT）寡核苷酸偶联的磁珠纯化聚（A）RNA。我们分别将HAV和NLV鉴定为I型基因型和II基因组菌株。两种病毒与亚洲菌株都有高度同源性。粪便大肠菌群分析显示，蛤肉中最可能数为93,000/100 g，约比贝类肉的卫生标准高300倍。
