Department of Surgery and Anaesthesiology of Domestic Animals, Faculty of Veterinary Medicine, Ghent University, Salisburylaan 133, 9820 Merelbeke, Belgium.
Vet J. 2013 Aug;197(2):415-9. doi: 10.1016/j.tvjl.2013.01.031. Epub 2013 Mar 7.
The increased incidence of methicillin-resistant Staphylococcus aureus (MRSA) infection in equine hospitals highlights the need for infection control protocols based on optimal patient screening. In horses, the deep ventral meatus of the nasal cavity is the principal site sampled to detect MRSA. However, in humans, the anterior nares are the preferred sampling site. The objective of this study was to determine the optimal sampling location in the nasal chambers for MRSA in horses by comparing the results obtained from three different locations (the vestibulum, diverticulum and ventral meatus) in 240 hospitalised animals. Antimicrobial susceptibility testing and epidemiological typing were conducted on representative subsets of the isolates obtained. Compared to the more invasive ventral meatus sampling (relative sensitivity 68.9%; isolation rate 37.9%), vestibulum (RS 81.1%; IR 44.6%, P=0.13) and diverticulum (RS 52.3%; IR 28.8%, P=0.03) sampling were more or less sensitive, respectively. In total, 132 horses (55%) were MRSA positive with the vast majority (98.5%) carrying genotyped isolates of the livestock-associated (LA)-MRSA clonal complex (CC) 398, and only a minority (1.5%) CC8. Of the 22 MLST typed isolates, five belonged to a novel ST2197 (t011, CC398). Although 93.9% of the isolates were multi-resistant (to β-lactam, tetracycline, trimethoprim, and gentamicin), <5% were resistant to virtually all antimicrobials commonly used in equine medicine. The study findings indicate that detection of MRSA in horses may be enhanced by replacing the traditional deep sampling of the ventral nasal meatus by the less invasive approach of sampling the nasal vestibulum.
耐甲氧西林金黄色葡萄球菌（MRSA）感染在马医院的发病率不断增加，这凸显了基于最佳患者筛选的感染控制方案的必要性。在马中，鼻腔的深部腹侧鼻道是检测 MRSA 的主要采样部位。然而，在人类中，前鼻孔是首选的采样部位。本研究的目的是通过比较 240 头住院动物的三个不同部位（前庭、憩室和腹侧鼻道）的结果，确定马鼻腔中用于检测 MRSA 的最佳采样部位。对获得的代表性分离株进行了抗菌药物敏感性测试和流行病学分型。与更具侵袭性的腹侧鼻道采样（相对敏感性 68.9%；分离率 37.9%）相比，前庭（RS 81.1%；IR 44.6%，P=0.13）和憩室（RS 52.3%；IR 28.8%，P=0.03）采样的敏感性更高或更低。总共 132 匹马（55%）被 MRSA 阳性，绝大多数（98.5%）携带基因型为牲畜相关（LA）-MRSA 克隆复合体（CC）398 的分离株，只有少数（1.5%）CC8。在 22 个 MLST 分型的分离株中，有 5 个属于新型 ST2197（t011，CC398）。尽管 93.9%的分离株对β-内酰胺、四环素、甲氧苄啶和庆大霉素具有多药耐药性，但<5%的分离株对马医学中常用的几乎所有抗菌药物具有耐药性。研究结果表明，通过用侵入性较小的鼻腔前庭采样替代传统的深部腹侧鼻道采样，可以提高马中 MRSA 的检测率。
