Department of Microbiology, Yekatit 12 Hospital Medical College, MCH building, 3rd floor, Room number 321, Addis Ababa, Ethiopia.
Department of Microbiology, Immunology and Parasitology; College of Health Sciences, Addis Ababa University, Addis Ababa, Ethiopia.
BMC Vet Res. 2020 Jan 22;16(1):20. doi: 10.1186/s12917-020-2235-8.
Staphylococcus aureus is a frequent colonizer of human and several animal species, including dairy cows. It is the most common cause of intramammary infections in dairy cows. Its public health importance increases inline to the continuous emergence of drug-resistant strains; such as Methicillin-resistant S. aureus (MRSA). Indeed, the recent emergence of human and veterinary adapted MRSA demands serious attention. The aim of this study was to determine the burden and drug resistance pattern of S. aureus in dairy farms in Mekelle and determine the molecular characteristics of MRSA.
This study was done on 385 lactating dairy cows and 71 dairy farmers. The ages of the cows and farmworkers were between 3 and 14 and 17-63 years respectively. S. aureus was isolated from 12.5% of cows and 31% of farmworkers. Highest resistance was observed for penicillin (> 90%) followed by tetracycline (32-35%) and trimethoprim-sulphamethoxazole (10-27%). But no resistance was observed for vancomycin, daptomycin, and rifampin. Only one isolate was MRSA both phenotypically and harboring mecA. This isolate was from nasal of a farmworker and was MRSA SCCmec Iva, spa type t064 of CC8. Multi-drug resistance was observed in 6.2% of cow isolates and 13.6% of nasal isolates.
In this study, S. aureus infected 12.5% of dairy cows and colonized 31% of farmworkers. Except for penicillin, resistance to other drugs was rare. Although no MRSA was found from dairy cows the existence of the human and animal adapted and globally spread strain, MRSA SCCmec IVa spa t064, warrants for a coordinated action to tackle AMR in both human and veterinary in the country.
金黄色葡萄球菌是人类和包括奶牛在内的几种动物物种的常见定植菌。它是奶牛乳腺炎最常见的病原体。随着耐药菌株的不断出现，如耐甲氧西林金黄色葡萄球菌（MRSA），其公共卫生重要性不断增加。事实上，最近出现的人兽共患和适应的 MRSA 需要引起高度重视。本研究旨在确定梅克尔（Mekelle）奶牛场金黄色葡萄球菌的负担和耐药模式，并确定 MRSA 的分子特征。
本研究共纳入 385 头泌乳奶牛和 71 名奶牛场工人。奶牛和农场工人的年龄分别在 3 至 14 岁和 17 至 63 岁之间。从 12.5%的奶牛和 31%的农场工人中分离出金黄色葡萄球菌。对青霉素（>90%）的耐药性最高，其次是四环素（32-35%）和甲氧苄啶-磺胺甲恶唑（10-27%）。但未观察到对万古霉素、达托霉素和利福平的耐药性。只有一个分离株是表型和 mecA 均为阳性的 MRSA。该分离株来自一名农场工人的鼻腔，为 SCCmec Iva 型、CC8 型 spa 型 t064。在奶牛分离株中观察到 6.2%和鼻腔分离株中 13.6%存在多药耐药。
在本研究中，金黄色葡萄球菌感染了 12.5%的奶牛，定植于 31%的农场工人。除青霉素外，其他药物的耐药性罕见。尽管未从奶牛中分离到 MRSA，但存在人兽共患和全球流行的耐甲氧西林金黄色葡萄球菌 SCCmec IVa spa t064 株，需要在该国的人类和兽医领域采取协调行动来应对 AMR。
