Dey Tushar K, Shome Bibek R, Bandyopadhyay Samiran, Goyal Naresh Kumar, Lundkvist Åke, Deka Ram P, Shome Rajeswari, Venugopal Nimita, Grace Delia, Sharma Garima, Rahman Habibar, Lindahl Johanna F
Department of Biosciences, International Livestock Research Institute, Nairobi 00100, Kenya.
Zoonosis Science Center, Department of Medical Biochemistry and Microbiology, Uppsala University, 75123 Uppsala, Sweden.
Pathogens. 2023 Feb 17;12(2):344. doi: 10.3390/pathogens12020344.
Bovine milk and milk products may contain pathogens, antimicrobial resistant bacteria, and antibiotic residues that could harm consumers. We analyzed 282 gram-positive isolates from milk samples from dairy farmers and vendors in Haryana and Assam, India, to assess the prevalence of methicillin-resistant staphylococci using microbiological tests, antibiotic susceptibility testing, and genotyping by PCR. The prevalence of genotypic methicillin resistance in isolates from raw milk samples was 5% [95% confidence interval, CI (3-8)], with 7% [CI (3-10)] in Haryana, in contrast to 2% [CI (0.2-6)] in Assam. The prevalence was the same in isolates from milk samples collected from farmers [5% ( = 6), CI (2-11)] and vendors [5% ( = 7), CI (2-10)]. Methicillin resistance was also observed in 15% of the isolates from pasteurized milk [( = 3), CI (3-38)]. Two staphylococci harboring a novel gene were identified for the first time in Indian dairy products. The only SCC type identified was Type V. The staphylococci with the ( = 11) gene in raw milk were commonly resistant to oxacillin [92%, CI (59-100)] and cefoxitin [74%, CI (39-94)], while the isolates with ( = 2) were resistant to oxacillin (100%) only. All the staphylococci with the ( = 3) gene in pasteurized milk were resistant to both oxacillin and cefoxitin. Our results provided evidence that methicillin-resistant staphylococci occur in dairy products in India with potential public health implications. The state with more intensive dairy systems (Haryana) had higher levels of methicillin-resistant bacteria in milk.
牛奶及奶制品可能含有会危害消费者的病原体、耐抗菌药物细菌及抗生素残留。我们分析了来自印度哈里亚纳邦和阿萨姆邦奶农及奶商牛奶样本中的282株革兰氏阳性菌分离株，通过微生物检测、抗生素敏感性检测及聚合酶链反应基因分型来评估耐甲氧西林葡萄球菌的流行情况。生牛奶样本分离株中基因型耐甲氧西林的流行率为5% [95%置信区间，CI(3 - 8)]，其中哈里亚纳邦为7% [CI(3 - 10)]，而阿萨姆邦为2% [CI(0.2 - 6)]。从奶农处[5% ( = 6), CI(2 - 11)]和奶商处[5% ( = 7), CI(2 - 10)]采集的牛奶样本分离株的流行率相同。在巴氏杀菌奶的分离株中也观察到15%存在耐甲氧西林情况[( = 3), CI(3 - 38)]。在印度奶制品中首次鉴定出两株携带新型基因的葡萄球菌。鉴定出的唯一葡萄球菌染色体盒（SCC）类型为V型。生牛奶中携带基因( = 11)的葡萄球菌通常对苯唑西林耐药[92%，CI(59 - 100)]，对头孢西丁耐药[74%，CI(39 - 94)]，而携带( = 2)的分离株仅对苯唑西林耐药(100%)。巴氏杀菌奶中所有携带( = 3)基因的葡萄球菌对苯唑西林和头孢西丁均耐药。我们的结果表明，印度奶制品中存在耐甲氧西林葡萄球菌，对公共卫生有潜在影响。奶制品体系更密集的邦（哈里亚纳邦）牛奶中耐甲氧西林细菌水平更高。
