福建省养殖环节牡蛎中诺如病毒污染状况分析

目的 了解福建省养殖环节牡蛎中诺如病毒(Norovirus)污染状况及基因分型,进一步定量分析诺如病毒污染水平,为食品中诺如病毒污染监测及安全风险评估提供数据支持。方法 2017年8月—2018年9月,于福建省某养殖基地采集牡蛎样品共244份,采用实时荧光定量聚合酶链式反应(PCR)法对样品中诺如病毒进行检测,确定其污染情况及基因分型。结果 211份有效样品中诺如病毒阳性率为30.33%(64/211),GI和GII组诺如病毒均有检出。GI组诺如病毒阳性率为16.59%(35/211),GII组阳性率为24.17%(51/211),GI和GII组同时为阳性的比例为10.43%(22/211)。诺如病毒含量在1.05×10²～1.68×10⁴基因拷贝/g(消化腺)之间。结论 福建省养殖环节牡蛎样品中存在诺如病毒污染,冬季阳性率较高,提示有关部门需在冬季采取更多针对性的风险管理干预措施,以降低食源性诺如病毒感染风险。

Survey of Norovirus in oysters collected from commercial harvesting farm in Fujian Province

Objective The contamination rate and gene groups of Norovirus (NoV) in oyster collected from harvesting farm in Fujian Province was investigated,and the contamination concentration was quantitatively analyzed, so as to provide data support for surveillance and risk assessment of Norovirus in food. Methods 244 oyster samples from oyster culture bed in Fujian Province were collected from August 2017 to September 2018. Norovirus nucleic acid was detected by real-time fluorescent quantitative polymerase chain reaction(PCR) to monitor Norovirus contamination in oyster production farm. Results The positive rate of Norovirus in 211 valid samples was 30.33% (64/211). Norovirus was detected in both GI and GII groups. 16.59%(35/211) of the samples were GI positive,24.17%(51/211) of the samples were GII positive, and 10.43%(22/211)of the samples were both GI and GII positive. The range of the quantity of Norovirus in positive samples was from 1.05×10²-1.68×10⁴ gene copies/g(digestive gland). Conclusion The oysters collected from commercial harvesting farm in Fujian Province were partly contaminated by Norovirus. A marked winter seasonality of contamination by both prevalence and quantity was observed.It is necessary to take more targeted risk management interventions in winter to reduce the risk of human illness resulting from Norovirus contamination of oysters.