2015-2019年上海市市售食品寄生虫感染监测分析

Surveillance and analysis of parasitic infection in food on market in Shanghai during 2015—2019

目的了解上海市市售食品寄生虫感染状况,为制订食品安全策略提供依据。方法根据城区、郊区结合的原则,2015—2019年对上海市部分农贸市场和超市的市售淡水类水产品、海水类水产品、腌制品类产品、肉类和蔬果类等食品进行抽样,分别采用压片法和消化法检测淡水类水产品和腌制品类产品中的寄生虫囊蚴,解剖镜检法检测海水类水产品中的异尖线虫幼虫,压片法检测肉类中的带绦虫囊尾蚴和旋毛虫幼虫囊包,荧光定量PCR方法检测肉类中弓形虫DNA,漂浮法检测蔬果类中的布氏姜片吸虫囊蚴和其他寄生虫虫卵。结果2015—2019年共检测市售淡水类水产品1125份,检出寄生虫囊蚴阳性9份,阳性率为0.8%。淡水鱼类585份,寄生虫囊蚴(华支睾吸虫)阳性率为1.5%(9/585),淡水鱼类中麦穗鱼的检出率较高(5/8);2015—2019年淡水鱼类阳性率分别为0.7%(1/144)、3.3%(4/121)、1.7%(2/120)、0(0/100)、2.0%(2/100)。淡水虾、蟹540份,未检出并殖吸虫囊蚴。检测海水类水产品35种591份,异尖线虫幼虫阳性率为31.1%(184/591),2015—2019年海水类水产品阳性率分别为36.0%(50/139)、37.1%(49/132)、29.2%(35/120)、39.0%(39/100)和11.0%(11/100)。青占鱼、小黄鱼和带鱼中异尖线虫幼虫的阳性率分别为72.5%(37/51)、70.1%(61/87)和50.0%(52/104),高于其他海鱼的19.1%(34/178)(χ^(2)=33.9、48.3、13.2,P<0.01)。检测腌制类样品443份,其中272份黄泥螺腌制品中查见棘口吸虫囊蚴,阳性率为61.4%(272/443),所有腌制类样品均未查见并殖吸虫囊蚴。检测猪、牛、羊、鸡、鸭等肉类样品253份,未检出猪带绦虫、牛带绦虫囊尾蚴,旋毛虫幼虫囊包和刚地弓形虫。检测蔬菜和可生食蔬果30份,均未检出布氏姜片吸虫囊蚴和其他寄生虫虫卵。结论2015—2019年上海市市售淡水类水产品、海水类水产品、腌制品类产品中存在有不同程度的寄生虫感染。

Objective To understand the status of parasitic infection in the food on market in Shanghai,in order to provide evidence for formulating strategies for food safety.Methods To carry out the surveillance,freshwater products,seawater products,pickled products,meat products and vegetables on farm product markets and supermarkets were sampled in Shanghai during 2015—2019,based on the combination of urban and suburb regions.The parasitic infection in the food samples were examined by using pressing method and digestion for detecting metacercariae in freshwater products and pickled products;using dissection microscopy for Anisakis larvae in seawater products;using pressing method for Taenia cysticercus and Trichinella encysted larvae in meat products;using fluorescent quantitative PCR for detecting Toxoplasma gondii DNA in the meat products;using the saline floating method for Fasciolopsis buski metacercaria or parasite eggs in vegetables.Results A total of 1125 samples of fresh water products were examined during 2015—2019,of which 9 were found of parasite metacercariae,with a positive rate of 0.8%.In the 585 freshwater fish samples,the positive rate of parasite metacercariae(Clonorchis sinensis)was 1.5%(9/585).The 540 samples of freshwater shrimps and crabs were not detected of Paragonimus metacercariae.Among freshwater fishes,the Pseudorasbora parve had the highest positive rate(5/8).The positive rates of parasite metacercaria in freshwater fishes were 0.7%(1/144),3.3%(4/121),1.7%(2/120),0(0/100)and2.0%(2/100)during 2015—2019,respectively.Anisakis larvae were found in 31.1%(184/591)of 591 samples of35 species of seawater products.The positive rates of Anisakis larvae in seawater fishes were 36.0%(50/139),37.1%(49/132),29.2%(35/120),39.0%(39/100)and 11.0%(11/100)during 2015—2019,respectively.The positive rate of Anisakis was higher in Pneumatophorus japonicas(72.5%,37/51),Larimichthys polyactis(70.1%,61/87)and Trichiurus lepturus(50.0%,52/104)than in other seawater products(19.1%,34/178)(χ^(2)=33.9,48.3,13.2;P<0.01).Among the 443 pickled products examined,272 pickled bullacta exarata products were infected with Echinostoma metacercariae,showing a positive rate of 61.4%,and none was detected with Paragonimus metacercariae.Of the 253 meat product samples of pigs,cattle,sheep,chickens and ducks,none was detected with Taenia solium metacercariae,Taenia saginata metacercariae,Trichinella larva cysts,or Toxoplasma spp.The 30 samples of vegetables were not detected with Fasciolopsis buski metacercaria or other parasite eggs.Conclusion There are different degrees of parasitic infection in freshwater products,seawater products and pickled products on the market in Shanghai.