Pediatric Department, Shaare-Zedek Medical Center, Jerusalem, IL, United States of America.
Neonatal Intensive Care Unit, Shaare-Zedek Medical Center, Jerusalem, IL, United States of America.
PLoS One. 2021 Sep 23;16(9):e0257821. doi: 10.1371/journal.pone.0257821. eCollection 2021.
Environmental surface sampling in healthcare settings is not routinely recommended. There are several methods for environmental surface sampling, however the yield of these methods is not well defined. The aim of the present study is to compare two methods of environmental surface sampling, to characterize the neonatal intensive care unit (NICU) flora, compare it with rates of infection and colonization and correlate it with the workload.
First, the yield of the swab and the gauze-pad methods were compared. Then, longitudinal surveillance of environmental surface sampling was performed over 6 months,once weekly, from pre-specified locations in the NICU. Samples were streaked onto selective media and bacterial colonies were identified using matrix-assisted laser desorption-ionization time-of-flight (MALDI-TOF).
The number of colonies isolated using the gauze pad method was significantly higher compared with the swab method. Overall, 87 bacterial species of 30 different bacterial genera were identified on the NICU environmental surfaces. Of these, 18% species were potential pathogens, and the other represent skin and environmental flora. In 20% of clinical cultures and in 60% of colonization cultures, the pathogen was isolated from the infant's environment as well. The number of bacteria in environmental cultures was negatively correlated with nurse/patient ratio in the day prior to the culture.
The gauze pad method for environmental sampling is robust and readily available. The NICU flora is very diverse and is closely related with the infants' flora, therefore it may serve as a reservoir for potential pathogens.
医疗机构环境表面采样并未常规推荐。有多种环境表面采样方法，但这些方法的效果尚未明确。本研究旨在比较两种环境表面采样方法，以描述新生儿重症监护病房（NICU）的菌群，并将其与感染和定植率进行比较，同时与工作量相关联。
首先，比较了拭子和纱布垫方法的效果。然后，对 NICU 中预先指定位置的环境表面进行为期 6 个月、每周一次的纵向监测采样。将样本划线接种于选择性培养基上，并使用基质辅助激光解吸电离飞行时间质谱（MALDI-TOF）鉴定细菌菌落。
纱布垫法分离的菌落数量明显高于拭子法。总体而言，NICU 环境表面共鉴定出 30 个不同细菌属的 87 种细菌。其中，18%的菌种为潜在病原体，其他则代表皮肤和环境菌群。20%的临床培养物和 60%的定植培养物中，病原体也从婴儿的环境中分离出来。培养前一天的护士与患者比例与环境培养物中的细菌数量呈负相关。
纱布垫法是一种可靠且易于获得的环境采样方法。NICU 的菌群非常多样化，与婴儿的菌群密切相关，因此它可能成为潜在病原体的储库。
