Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267, Université de Poitiers, Poitiers, France; Bâtiment Urgences et Biologie Médicale (UBM), CHU de Poitiers, Poitiers, France.
Equipe Microbiologie de l'Eau, Ecologie et Biologie des Interactions, Centre National de la Recherche Scientifique UMR 7267, Université de Poitiers, Poitiers, France.
Water Res. 2015 Sep 15;81:223-31. doi: 10.1016/j.watres.2015.05.065. Epub 2015 Jun 3.
Some infections cases due to exposure to output water from dental unit waterlines (DUWL) have been reported in the literature. However, this type of healthcare-associated risk has remained unclear and up until now the overall bacterial composition of DUWL has been poorly documented. In this study, 454 high-throughput pyrosequencing was used to investigate the bacterial community in seven dental offices (N = 7) and to identify potential bacterial pathogenic sequences. Dental unit waters (DUW) were collected from the tap water supplying units (Incoming Water; IW) to the output exposure point of the turbine handpiece (Output water; OW) following a stagnation period (OWS), and immediately after the last patient of the sampling day (OWA). A high bacterial diversity was revealed in DUW with 394 operational taxonomic units detected at the genus level. In addition to the inter-unit variability observed, results showed increased total bacterial cell concentration and shifts in bacterial community composition and abundance at the genus level, mainly within the Gamma- and Alpha-Proteobacteria class, as water circulated in the dental unit (DU). Results showed that 96.7%, 96.8% and 97.4% of the total sequences from IW, OWS and OWA respectively were common to the 3 defined water groups, thereby highlighting a common core microbiome. Results also suggested that stagnation and DU maintenance practices were critical to composition of the bacterial community. The presence of potentially pathogenic genera was detected, including Pseudomonas and Legionella spp. Emerging and opportunistic pathogenic genera such as Mycobacterium, Propionibacterium and Stenotrophomonas were likewise recovered in DUW. For the first time, an exhaustive evaluation of the bacterial communities present in DUW was performed taking into account the circulation of water within the DU. This study highlights an ignored diversity of the DUWL bacterial community. Our findings also contribute to a better appreciation of the potential infectious risk associated with dental care and suggest the importance of better managing microbial quality in DUW.
一些由于暴露于牙科手机供水水路（DUWL）出水而导致的感染病例已在文献中报道。然而，这种类型的与医疗保健相关的风险仍不清楚，到目前为止，DUWL 的总体细菌组成仍记录不佳。在这项研究中，使用 454 高通量焦磷酸测序技术对 7 家牙科诊所（N=7）的细菌群落进行了研究，并鉴定了潜在的细菌致病序列。牙科手机用水（DUW）从向涡轮机头出水点供水的单元供水（进水管路水，IW）中采集，在停滞期（OWS）后和采样日最后一位患者后的即刻（OWA）。DUW 中显示出很高的细菌多样性，在属水平上检测到 394 个操作分类单元。除了观察到的单元间变异性外，结果还显示，随着水在牙科手机中循环，总细菌细胞浓度增加，细菌群落组成和丰度发生变化，主要在 Gamma-和 Alpha-Proteobacteria 类中。结果表明，IW、OWS 和 OWA 中分别有 96.7%、96.8%和 97.4%的总序列与 3 个定义的水样组共有，从而突出了一个共同的核心微生物组。结果还表明，停滞和牙科手机维护实践对细菌群落的组成至关重要。检测到潜在致病性属的存在，包括假单胞菌属和军团菌属。同样，在 DUW 中也回收了新兴和机会性致病属，如分枝杆菌属、丙酸杆菌属和寡养单胞菌属。首次对考虑牙科手机内水的循环时 DUWL 中存在的细菌群落进行了详尽的评估。本研究突出了牙科手机供水水路细菌群落被忽视的多样性。我们的研究结果也有助于更好地了解与牙科护理相关的潜在感染风险，并表明在 DUW 中更好地管理微生物质量的重要性。
