Department of Clinical Sciences, Faculty of Veterinary Medicine and Animal Science, Swedish University of Agricultural Sciences, 750 07, Uppsala, Sweden.
Department of Animal Health and Antimicrobial Strategies, Swedish Veterinary Agency, 751 89, Uppsala, Sweden.
Acta Vet Scand. 2024 Sep 2;66(1):43. doi: 10.1186/s13028-024-00768-4.
Environmental bacteria in animal healthcare facilities may constitute a risk for healthcare-associated infections (HAI). Knowledge of the bacterial microflora composition and factors influencing the environmental bacterial load can support tailored interventions to lower the risk for HAI. The aims of this study were to: (1) quantify and identify environmental bacteria in one operating room (OR) and one ultrasound room (UR) in a small animal hospital, (2) compare the bacterial load to threshold values suggested for use in human healthcare facilities, (3) characterise the genetic relationship between selected bacterial species to assess clonal dissemination, and (4) investigate factors associated with bacterial load during surgery. Settle plates were used for passive air sampling and dip slides for surface sampling. Bacteria were identified by Matrix Assisted Laser Desorption-Time Of Flight. Antimicrobial susceptibility was determined by broth microdilution. Single nucleotide polymorphism-analysis was performed to identify genetically related isolates. Linear regression was performed to analyse associations between observed explanatory factors and bacterial load.
The bacterial load on settle plates and dip slides were low both in the OR and the UR, most of the samples were below threshold values suggested for use in human healthcare facilities. All settle plates sampled during surgery were below the threshold values suggested for use in human clean surgical procedures. Staphylococcus spp. and Micrococcus spp. were the dominating species. There was no indication of clonal relationship among the sequenced isolates. Bacteria carrying genes conveying resistance to disinfectants were revealed. Air change and compliance with hygiene routines were sufficient in the OR. No other factors possibly associated with the bacterial load were identified.
This study presents a generally low bacterial load in the studied OR and UR, indicating a low risk of transmission of infectious agents from the clinical environment. The results show that it is possible to achieve bacterial loads below threshold values suggested for use in human healthcare facilities in ORs in small animal hospitals and thus posing a reduced risk of HAI. Bacteria carrying genes conveying resistance to disinfectants indicates that resistant bacteria can persist in the clinical environment, with increased risk for HAI.
动物保健设施中的环境细菌可能对医源性感染（HAI）构成威胁。了解细菌菌群组成和影响环境细菌负荷的因素，可以支持采取有针对性的干预措施，降低 HAI 的风险。本研究的目的是：（1）量化和鉴定一家小动物医院的一个手术室（OR）和一个超声室（UR）中的环境细菌，（2）将细菌负荷与建议用于人类保健设施的阈值进行比较，（3）对选定的细菌物种的遗传关系进行特征描述，以评估克隆传播，以及（4）调查手术期间与细菌负荷相关的因素。沉降平板用于被动空气采样，浸棒用于表面采样。通过基质辅助激光解吸飞行时间（MALDI-TOF）进行细菌鉴定。通过肉汤微量稀释法测定抗生素敏感性。通过单核苷酸多态性分析鉴定遗传相关的分离株。进行线性回归分析以分析观察到的解释因素与细菌负荷之间的关联。
OR 和 UR 中的沉降平板和浸棒上的细菌负荷均较低，大多数样本低于建议用于人类保健设施的阈值。手术期间采集的所有沉降平板均低于建议用于人类清洁手术程序的阈值。葡萄球菌属和微球菌属是主要的物种。测序分离株之间没有克隆关系的迹象。发现了携带赋予消毒剂抗性基因的细菌。OR 中的空气交换和遵守卫生常规是充分的。未确定其他可能与细菌负荷相关的因素。
本研究表明，在所研究的 OR 和 UR 中，细菌负荷普遍较低，表明从临床环境传播感染因子的风险较低。结果表明，在小动物医院的 OR 中，有可能实现低于建议用于人类保健设施的阈值的细菌负荷，从而降低 HAI 的风险。携带赋予消毒剂抗性基因的细菌表明，抗性细菌可能在临床环境中持续存在，HAI 的风险增加。
