2009-2014年马鞍山市食品中李斯特菌污染状况调查

The investigation of Listeria species in food products in Maanshan during 2009 to 2014

目的了解马鞍山市食品中李斯特菌污染状况。方法 2009年1月至2014年12月,对马鞍山市部分餐饮店、超市及零售市场中的12类食品(包括畜肉、禽肉、鱼虾、动物内脏、熟食制品、蔬菜、米面制品、豆制品、禽蛋、果汁、乳制品、冷饮)进行随机抽样,共采集2 372份样品进行李斯特菌分离检测,并对检出的单增李斯特菌进行了毒力基因检测。结果2 372份样品中332份存在李斯特菌,检出率为14.00%,其中畜肉检出率为25.15%(82/326),禽肉为23.98%(82/342),鱼虾为16.20%(104/642),动物内脏为11.66%(26/223),熟食为8.49%(31/365),蔬菜为2.88%(4/139),米面制品为2.20%(2/91),豆制品为1.33%(1/75),各类食品李斯特菌检出率比较,差异有统计学意义(χ~2=65.64,P<0.05),禽蛋、果汁、乳制品、冷饮中未检出李斯特菌。2009年李斯特菌的检出率最高(23.97%,70/292),其次分别为2011年(15.62%,67/429),2012年(15.36%,49/319),2014年(11.65%,48/412),2013年(11.11%,47/423),2010年(10.26%,51/497),各年度食品中李斯特菌检出率比较差异有统计学意义(χ~2=26.80,P<0.05)。对检出的48株单增李斯特菌进行6个毒力基因(hly、prfA、plcB、inlA、actA和iap)的聚合酶链式反应(PCR)检测,结果显示所有分离菌株均具有6个毒力基因。结论马鞍山市食品存在不同程度的李斯特菌污染,具有食源性李斯特菌感染疾病暴发的潜在风险,应加强监督监测,预防李斯特菌所引起的食源性疾病发生。

Objective The aim of this study was to determine the prevalence of Listeria species in food products in Maanshan,Anhui Province. Methods From January 2009 to December 2014,a total of 2 372 food products,including meat,poultry,fishes,shrimps,animal viscera,cooked food,vegetables,flour products,bean products,eggs,juice,dairy products and ice creams,were randomly collected from restaurants,supermarkets and retail markets in Maanshan.Listeria spp. strains were isolated according to GB 4789. 30-2010 method. Furthermore,all the Listeria monocytogenes were examined for the presence of virulence genes. Results Out of 2 372 tested samples,332（ 14. 00 %） were contaminated with Listeria spp.,of which 25. 15 %（ 82/326） were isolated from meats,23. 98 %（ 82/342） from poultry meats,16. 20 %（ 104/642） from fishes and shrimps,11. 66 %（ 26/223） from animal viscera,8. 49 %（ 31/365） from cooked food,2. 88 %（ 4/139） from vegetables,2. 20 %（ 2/91） from flour products and 1. 33 %（ 1/75） from bean products.There was no Listeria spp. isolated in eggs,juice,dairy products and ice creams. The highest prevalence of Listeria spp.occurred in 2009（ 23. 97 %,70/292）, followed by 2011（ 15. 62 %,67/429）,2012（ 15. 36 %,49/319）,2014（ 11. 65%,48/412）,2013（ 11. 11%,47/423） and 2010（ 10. 26%,51/497）. The difference of the prevalence rates of Listeria for different years were statistically significant（ χ~2= 26. 80,P〈 0. 05）. Six virulence genes,including hly,prfA,plcB,inlA, actA and iap, were observed in all of the L. monocytogenes isolates. Conclusion There were different contamination levels of Listeria in different food and years in Maanshan. This study revealed the potential risk of foodbornedisease outbreak caused by L. monocytogenes. Persistent surveillance on the contamination of Listeria spp. in food products should be strengthened to prevent foodborne listeriosis.