Department of Plant Science and Landscape Architecture, University of Maryland, College Park, Maryland, USA.
Maryland Institute of Applied and Environmental Health, School of Public Health, University of Maryland, College Park, Maryland, USA.
J Appl Microbiol. 2022 Aug;133(2):477-487. doi: 10.1111/jam.15570. Epub 2022 Apr 20.
To evaluate the safety of irrigation water sources based on phenotypic antimicrobial resistance (AMR) in Enterococcus spp., a potential environmental reservoir for AMR determinants.
Eleven sites representing fresh and brackish water rivers, ponds and reclaimed water, were sampled over 2 years. Samples (n = 333) yielded 198 unique isolates of Ent. faecalis and Ent. faecium which were tested for antimicrobial susceptibility by microbroth dilution. Species distribution was influenced by water type and season. Enterococcus faecalis was more likely found in freshwater rivers and in summer, and Ent. faecium in reclaimed water and in spring. Only 11% of isolates were pansusceptible, while 48.5% and 26.3% were single (SDR) and multidrug resistant (MDR), respectively. MDR was more likely detected in Ent. faecium than Ent. faecalis. Winter isolates were more likely than summer isolates to exhibit MDR than SDR.
Enterococcus faecalis and Ent. faecium in surface and reclaimed water exhibited diverse phenotypic AMR and a low-level resistance to clinically important antimicrobials such as ampicillin, vancomycin and linezolid.
Single and multidrug resistance in E. faecalis and E. faecium varied by season but not water type. Antimicrobial resistance prevalence can assist decisions on the safety of irrigation water sources for fresh produce crops.
评估基于肠球菌属（Enterococcus spp.）表型抗菌药物耐药性（AMR）的灌溉用水源安全性，肠球菌属是 AMR 决定因素的潜在环境储库。
在 2 年期间，从代表淡水和咸水河流、池塘和再生水的 11 个地点采集样本。对 333 个样本进行了分离培养，获得了 198 个独特的粪肠球菌和屎肠球菌分离株，并通过微量肉汤稀释法进行了抗菌药物敏感性测试。物种分布受水源类型和季节的影响。粪肠球菌更可能在淡水河流和夏季中被发现，屎肠球菌则更可能在再生水中和春季中被发现。只有 11%的分离株表现为全敏感，而 48.5%和 26.3%分别为单耐药（SDR）和多药耐药（MDR）。屎肠球菌比粪肠球菌更容易出现 MDR。冬季分离株比夏季分离株更有可能表现出 MDR 而不是 SDR。
地表水和再生水中的粪肠球菌和屎肠球菌表现出多样化的表型 AMR，对临床重要的抗菌药物（如氨苄西林、万古霉素和利奈唑胺）具有低水平的耐药性。
粪肠球菌和屎肠球菌的单药和多药耐药性因季节而异，但与水源类型无关。抗菌药物耐药性的流行情况有助于为新鲜农产品作物的灌溉用水源安全性做出决策。
