湖南省动物源性食品中沙门菌流行特征分析

Epidemiological characteristics of Salmonella in animal source foods in Hunan

目的 研究湖南省动物源性食品中沙门菌的分子流行病学特征.方法 2010年在湖南省10个市的集贸市场和超市,按照无菌采样原则采集畜肉159份、禽肉152份,动物性水产品381份,共计692份样品,分离沙门菌,进行血清、耐药表型和PFGE分子分型.结果 692份动物源性食品中,93份样品检出沙门菌,检出率为13.4％,禽肉、畜肉和水产品中沙门菌检出率分别为23.0％ （35/152）,22.6％ （36/159）和5.8％（22/381）,水产品中沙门菌检出率低于禽肉和畜肉（x2值分别为33.86、33.29,P值均＜0.05）.分离菌株血清型呈多样化分布,优势血清型为德尔卑沙门菌,占35.1％（33/94）.79.8％ （75/94）的菌株至少对一种抗生素耐药,31.9％ （30/94）的菌株对5种以上抗生素耐药,呈多重耐药性,禽、畜肉中分离菌株的多重耐药率分别为47.2％ （17/36）和22.2％（8/36）,禽肉分离的多重耐药菌株高于畜肉（x2=4.96,P＜0.05）.试验菌株对四环素的耐药率最高,达62.8％（59/94）.PFGE分型可以分为69个PFGE型,优势型为7型（6株）、15型（4株）和22型（6株）.结论 湖南省动物源性食品沙门菌污染严重,且菌株耐药形势严峻,PFGE分型结果提示可能存在沙门菌流行株.

Objective To study the molecular epidemiological characteristics of Salmonella in animal source foods in Hunan.Methods The fair trade markets and supermarkets of ten cities were chosen to sample animal source foods for isolating Salmonella in Hunan province in 2010.A total of 692 samples were collected by aseptic sampling,included 159 livestock meats,152 poultry meats,and 381 aquatic products.Salmonella strains isolated were subjected to stereotyping,antimicrobial susceptibility testing and pulsed field gel electrophoresis （PFGE）.Results Salmonella was detected in 93 of 692 animal food samples with the detection rate of 13.4%.The detection rates of Salmonella in poultry meats,livestock meats and aquatic products were 23.0% （35/152）,22.6% （36/159） and 5.8% （22/381） respectively.Therefore,the detection rate in aquatic products was lower than that of poultry meats and livestock meats （x2 =33.86,P 〈 0.05 ; x2 =33.29,P 〈 0.05,respectively）.The serotypes of isolates showed diversity,and Salmonella Derby（33/94,35.1%） was the predominant serotypes.79.8% （75/94） strains showed resistant to more than one antibiotic used in the test,31.9% （30/94） strains showed resistant to more than 5 antibiotics.A significant difference was observed for multidrug resistance between Salmonella isolated from poultry（47.2%,17/36） and livestock meats （22.2%,8/36） （x2 =4.96,P 〈 0.05）.And the highest resistant rate was found in tetracycline,as high as 62.8% （59/94）.All the strains were divided into 69 PFGE subtypes.Furthermore the dominating subtypes were type 7 （6 strains）,type 15 （4 strains）,type 22 （6 strains）.Conclusion Inspection results showed that Salmonella contamination in animal source foods were serious in Hunan province,and the isolates expressed high level resistance to the antibiotics.Furthermore the PFGE results indicated that there were epidemic strains of Salmonella in Hunan.