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[目的]了解上海市松江区婴幼儿食品中阪崎肠杆菌的污染状况、分子分型及耐药性,为婴幼儿食品安全管理和食源性疾病的预警及临床用药提供科学依据。[方法]2016年选择松江区3个街道和4个乡镇,共19家食品店或超市,采集婴幼儿配方奶粉(包括乳基、豆基)、婴幼儿谷类辅助食品和适用于婴幼儿的固体饮料,共124件。依据GB 4789.40—2010《食品安全国家标准食品微生物学检验阪崎肠杆菌检验》检验程序及荧光定量PCR方法,对所采集样品进行阪崎肠杆菌的分离培养鉴定及血清分型,并进一步进行药物敏感性试验;采用脉冲场凝胶电泳(PFGE)技术进行分子分型。[结果]124件样品中:婴幼儿谷类辅食51件,检出阪崎肠杆菌11株(9株保存成功),阳性率为21.6%;婴幼儿配方奶粉53件、固体饮料20件,均未检出阪崎肠杆菌;3类食品中阪崎肠杆菌检出率的差异有统计学意义(P<0.01)。采用PCR方法验证阳性菌,符合率为100%。9株阳性菌血清分型显示3株O1群,6株O2群。药敏试验结果显示,在所测定的16种抗生素中,9株阪崎肠杆菌只对头孢唑啉中度耐药或耐药,对其他抗生素均敏感。PFGE分子分型结果显示9株阪崎肠杆菌分为5种PFGE型别,相似度范围在50%~100%;其中A型有4株,B型有2株,相似度均为100%。[结论]上海市松江区婴幼儿谷类辅食中阪崎肠杆菌的阳性率高于其他类婴幼儿食品。阪崎肠杆菌对测定的抗生素(除头孢唑啉外)均敏感,其血清分型主要为O1、O2群,PFGE分型显示不同或相同品牌婴幼儿辅食中阪崎肠杆菌有同源性,可应用于阪崎肠杆菌的溯源。
[Objective] To understand the status, molecular typing and drug resistance of Enterobacter sakazakii in infants and young children’s food in Songjiang District of Shanghai, and to provide a scientific basis for the early warning and clinical medication of infant food safety management and food-borne diseases. [Method] In 2016, a total of 19 food stores or supermarkets were selected in 3 streets and 4 townships in Songjiang District to collect infant formula (including milk-based and soy-based), cereal supplements for infants and young children, and solids suitable for infants and young children Drinks, a total of 124. According to GB 4789.40-2010 “National Food Safety Standard Microbiological Examination of Enterobacter sakazakii test” test program and fluorescent quantitative PCR method, the collected samples of Enterobacter sakazakii isolated culture identification and serotyping, and further drugs Sensitivity test; Molecular typing by pulsed-field gel electrophoresis (PFGE). [Result] Among 124 samples, 51 infant and young cereal supplementary foods were detected, 11 strains of Enterobacter sakazakii were detected (9 strains were successfully preserved), the positive rate was 21.6%, 53 infant formulas and 20 solid drinks, none of which Enterobacter sakazakii was detected. The detection rate of Enterobacter sakazakii in three kinds of food was statistically significant (P <0.01). The PCR method was used to verify the positive bacteria, the coincidence rate was 100%. Serotypes of 9 positive bacteria showed 3 strains of O1 and 6 strains of O2. Susceptibility test results showed that of the 16 antibiotics tested, 9 Enterobacter sakazakii were moderately resistant or resistant to cefazolin and sensitive to the other antibiotics. PFGE molecular typing results showed that 9 strains of Enterobacter sakazakii were divided into 5 PFGE types, with the similarities ranging from 50% to 100%. Among them, 4 strains were type A and 2 strains were type B, all with similarities of 100%. [Conclusion] The positive rate of Enterobacter sakazakii in infant cereal supplementary food in Songjiang District of Shanghai was higher than that of other kinds of infant food. Enterobacter sakazakii was sensitive to the antibiotics (except cefazolin), the serotypes were mainly O1 and O2, PFGE typing showed homologous to Enterobacter sakazakii in different or same-brand infant food, Can be applied to E. sakazakii traceability.