Greenstein Abigail W, Boyle-Vavra Susan, Maddox Carol W, Tang Xiwei, Halliday Lisa C, Fortman Jeffrey D
Comp Med. 2019 Aug 1;69(4):311-320. doi: 10.30802/AALAS-CM-18-000089. Epub 2019 Aug 2.
Methicillin-resistant (MRSA) carriage and infection are well documented in the human and veterinary literature; however only limited information is available regarding MRSA carriage and infection in laboratory NHP populations. The objective of this study was to characterize MRSA carriage in a representative research colony of rhesus and cynomolgus macaques through a cross-sectional analysis of 300 animals. MRSA carriage was determined by using nasal culture. Demographic characteristics of carriers and noncarriers were compared to determine factors linked to increased risk of carriage, and MRSA isolates were analyzed to determine antimicrobial susceptibility patterns, staphylococcal chromosome cassette mec (SCCmec) type, and multilocus sequence type (ST). Culture results demonstrated MRSA carriage in 6.3% of the study population. Animals with greater numbers of veterinary or experimental interventions including antibiotic administration, steroid administration, dental procedures, and surgery were more likely to carry MRSA. Susceptibility results indicated that MRSA isolates were resistant to β-lactams, and all isolates were resistant to between 1 and 4 non β-lactam antibiotics. In addition, 73.7% of MRSA isolates were identified as ST188-SCCmec IV, an isolate previously observed in an unrelated population of macaques and 15.8% were ST3268-SCCmec V, which has only been described in macaques. A single isolate had a novel sequence type, ST3478, and carried SCCmec V. These results suggest that NHP-adapted strains of MRSA exist and highlight the emergence of antimicrobial resistance in laboratory NHP populations.
耐甲氧西林金黄色葡萄球菌（MRSA）的携带和感染在人类和兽医文献中有充分记载；然而，关于实验室非人灵长类动物群体中MRSA携带和感染的信息却很有限。本研究的目的是通过对300只动物的横断面分析，描述恒河猴和食蟹猴代表性研究群体中MRSA的携带情况。采用鼻腔培养法确定MRSA携带情况。比较携带者和非携带者的人口统计学特征，以确定与携带风险增加相关的因素，并分析MRSA分离株以确定抗菌药物敏感性模式、葡萄球菌染色体盒mec（SCCmec）类型和多位点序列类型（ST）。培养结果显示，研究群体中有6.3%携带MRSA。接受更多兽医或实验干预（包括抗生素给药、类固醇给药、牙科手术和手术）的动物更有可能携带MRSA。药敏结果表明，MRSA分离株对β-内酰胺类耐药，所有分离株对1至4种非β-内酰胺类抗生素耐药。此外，73.7%的MRSA分离株被鉴定为ST188-SCCmec IV，该分离株先前在无关的猕猴群体中观察到，15.8%为ST3268-SCCmec V，仅在猕猴中描述过。一株分离株具有新的序列类型ST3478，并携带SCCmec V。这些结果表明存在适应非人灵长类动物的MRSA菌株，并突出了实验室非人灵长类动物群体中抗菌药物耐药性的出现。
