Hayer Shivdeep Singh, Rovira Albert, Olsen Karen, Johnson Timothy J, Vannucci Fabio, Rendahl Aaron, Perez Andres, Alvarez Julio
Department of Veterinary Population Medicine, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA.
Veterinary Diagnostic Laboratory, College of Veterinary Medicine, University of Minnesota, St. Paul, MN, USA.
Transbound Emerg Dis. 2020 Sep;67(5):1930-1941. doi: 10.1111/tbed.13528. Epub 2020 Mar 12.
Antimicrobial resistance (AMR) is an emerging threat to both human and animal health. Antimicrobial use and resistance in food animal production, including swine, has received increased scrutiny as a source of resistant foodborne pathogens. Continuous surveillance of AMR in bacterial isolates of swine origin can guide in conservation of antimicrobials used in both human and swine medicine. The objective of this study was to evaluate the prevalence and trends of the phenotypic AMR in Escherichia coli of swine origin isolated from clinical samples at the Minnesota Veterinary Diagnostic laboratory between 2006 and 2016. The prevalence of resistance to ampicillin, tetracyclines and sulphadimethoxine remained greater than 50% throughout the period. There was a drastic change in enrofloxacin resistance, increasing from less than 1% to more than 20% between 2006 and 2016 (annual relative increase of 57% between 2006 and 2013 and 16% between 2013 and 2016). The prevalence of resistance to other antimicrobials remained constant (ceftiofur, oxytetracycline and chlortetracycline) or changed significantly (annual relative changes of less than 10%) for at least some time-period between 2006 and 2016 (ampicillin, florfenicol, gentamicin, neomycin, sulphadimethoxine, trimethoprim-sulphamethoxazole and spectinomycin). Rarefaction analysis revealed an increase in the number of unique combinations of AMRs per year. Network analysis was performed by estimating and plotting partial correlations between minimum inhibitory concentrations (MICs) of various antimicrobials. An increase in strength of these networks was observed, particularly in networks created after 2010, which can be indicative of increased multiple AMR in these isolates. These results provide valuable insight into the trends in AMR in E. coli of swine origin in the USA and act as supplementary information to the existing active AMR surveillance systems.
抗菌药物耐药性（AMR）对人类和动物健康都是一种新出现的威胁。包括猪在内的食用动物生产中的抗菌药物使用和耐药性，作为耐药食源性病原体的一个来源，受到了越来越多的审查。持续监测猪源细菌分离株中的AMR可以指导人类和猪用抗菌药物的合理使用。本研究的目的是评估2006年至2016年期间从明尼苏达兽医诊断实验室的临床样本中分离出的猪源大肠杆菌中表型AMR的流行情况和趋势。在此期间，对氨苄西林、四环素和磺胺二甲氧嘧啶的耐药率一直保持在50%以上。恩诺沙星耐药性发生了急剧变化，2006年至2016年间从不到1%增加到超过20%（2006年至2013年期间年相对增长率为57%，2013年至2016年期间为16%）。对其他抗菌药物的耐药率保持不变（头孢噻呋、土霉素和金霉素），或在2006年至2016年期间至少有一段时间发生显著变化（年相对变化小于10%）（氨苄西林、氟苯尼考、庆大霉素、新霉素、磺胺二甲氧嘧啶、甲氧苄啶-磺胺甲恶唑和壮观霉素）。稀疏分析显示每年AMR独特组合的数量有所增加。通过估计和绘制各种抗菌药物的最低抑菌浓度（MIC）之间的偏相关性进行网络分析。观察到这些网络的强度有所增加，特别是在2010年后创建的网络中，这可能表明这些分离株中多重AMR增加。这些结果为美国猪源大肠杆菌中AMR的趋势提供了有价值的见解，并作为现有主动AMR监测系统的补充信息。
