Department of Urban Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8654, Japan.
Lett Appl Microbiol. 2023 Aug 2;76(8). doi: 10.1093/lambio/ovad090.
Waterborne disease is increasingly becoming associated with opportunistic premise plumbing pathogens (OPPPs), which can resist residual chlorination, regrow throughout drinking water distribution systems, and colonize premise plumbing. Nontuberculous mycobacteria (NTM) include clinically important species and exert a high burden on healthcare systems. We briefly report a qPCR-based survey of Mycobacterium spp. numbers in tap, POU-treated, and shower waters from Bangkok, Thailand. Non-stagnant tap waters and non-stagnant shower waters had mean numbers of 1.3 × 103 and 2.4 × 103 copies/mL, respectively. Water stagnation resulted in mean numbers higher by up to 1.0 log. The lowest number, 25 copies/mL, was obtained from a POU-treated sample, while the highest number, 2.0 × 104 copies/mL, came from a stagnant tap. Comparing with international data, mean numbers in this study were greater than those in nine out of 11 (82%) comparable studies, and the maximum numbers in this study were also high. Our samples of Bangkok waters exhibited relatively high Mycobacterium spp. numbers, suggesting the need for appropriate POU treatment systems where NTM infection is a health concern. This survey data can be used to set inactivation performance targets in POU water disinfection system design and may also lead to quantitative microbial risk assessment (QMRA) studies.
水媒疾病与机会性前提管道病原体（OPPPs）的关联性日益增加，这些病原体能够抵抗余氯，在饮用水分配系统中重新生长，并在前提管道中定植。非结核分枝杆菌（NTM）包括临床上重要的物种，对医疗保健系统造成了高负担。我们简要报告了一项基于 qPCR 的泰国曼谷 taps、POU 处理水和淋浴水中分枝杆菌属数量的调查。非静止 taps 水和非静止淋浴水的平均数量分别为 1.3×103 和 2.4×103 拷贝/mL。水静止会导致数量平均增加多达 1.0 个对数。从 POU 处理的样品中获得的最低数量为 25 拷贝/mL，而最高数量为 2.0×104 拷贝/mL，来自静止 taps。与国际数据相比，本研究中的平均数量大于 11 个可比研究中的 9 个（82%），本研究中的最高数量也很高。我们的曼谷水样显示出相对较高的分枝杆菌属数量，表明需要在 NTM 感染是健康问题的情况下，使用适当的 POU 处理系统。这些调查数据可用于设定 POU 水消毒系统设计中的灭活性能目标，也可能导致定量微生物风险评估（QMRA）研究。
