BACKGROUND 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. RESULTS 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. CONCLUSIONS 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.

中文翻译：

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埃塞俄比亚北部Mekelle奶牛场的金黄色葡萄球菌的负担和抗药性。

背景技术金黄色葡萄球菌是人类和几种动物物种（包括奶牛）的频繁定居者。它是奶牛乳房内感染的最常见原因。随着对耐药菌株的不断出现，其对公共卫生的重要性日益提高。如耐甲氧西林的金黄色葡萄球菌（MRSA）。确实，最近出现的人类和兽医适应性MRSA需要引起高度重视。这项研究的目的是确定梅克勒（Mekelle）奶牛场中金黄色葡萄球菌的负担和耐药模式，并确定MRSA的分子特征。结果本研究是在385头泌乳奶牛和71头奶牛养殖者身上进行的。奶牛和农场工人的年龄分别为3至14岁和17-63岁。从12.5％的奶牛和31％的农场工人中分离出金黄色葡萄球菌。青霉素（> 90％），四环素（32-35％）和甲氧苄啶-磺基甲恶唑（10-27％）的耐药性最高。但是未观察到万古霉素，达托霉素和利福平耐药。无论是表型还是带有mecA的MRSA都只有一种。该分离物来自农场主的鼻，是MRSA SCCmec Iva，CC8的温泉类型t064。在6.2％的牛分离株和13.6％的鼻分离株中观察到多药耐药性。结论在本研究中，金黄色葡萄球菌感染了12.5％的奶牛，并定居了31％的农场工人。除青霉素外，对其他药物的耐药性极少。尽管未从奶牛中发现MRSA，但存在人类和动物适应的且在全球范围内传播的毒株，MRSA SCCmec IVa spa t064仍需要采取协调一致的行动来解决该国人类和兽医的AMR。