United States Environmental Protection Agency, Cincinnati, OH, 45268, USA.
United States Environmental Protection Agency, Region 6, Dallas, TX, 75270, USA.
Int J Hyg Environ Health. 2022 Aug;245:114023. doi: 10.1016/j.ijheh.2022.114023. Epub 2022 Sep 1.
To observe how Legionella pneumophila, the causative agent for legionellosis, can transmit through the hot water plumbing of residences and office buildings.
Using qPCR, L. pneumophila and L. pneumophila Serogroup (Sg)1 were measured in hot water samples collected from 100 structures, consisting of 70 residences and 30 office buildings. The hot water samples collected from office buildings had a higher L. pneumophila detection frequency of 53% (16/30) than residences, with a 10 GU/L (median) concentration. An office building's age was not a statistically significant predictor of contamination, but its area (>100,000 sq. ft.) was, P = <0.001. Hot water samples collected at residences had a lower L. pneumophila detection frequency of 36% (25/70) than office buildings, with a 100 GU/L (median) concentration. A residence's age was a significant predictor of contamination, P = 0.009, but not its area. The water's secondary disinfectant type did not affect L. pneumophila detection frequency nor its concentration in residences, but the secondary disinfectant type did affect results in office buildings. Legionella pneumophila's highest detection frequencies were in samples collected in March-August for office buildings and in June-November for residences.
This study revealed that the built environment influences L. pneumophila transport and fate. Residential plumbing could be a potential "conduit" for L. pneumophila exposure from a source upstream of the hot water environment. Both old and newly built office buildings had an equal probability of L. pneumophila contamination. Legionella-related remediation efforts in office buildings (that contain commercial functions only) might not significantly improve a community's public health.
观察嗜肺军团菌（军团病的病原体）如何通过住宅和办公楼的热水管道传播。
使用 qPCR 方法，从 100 个建筑物（包括 70 个住宅和 30 个办公楼）收集的热水样本中测量了嗜肺军团菌和嗜肺军团菌血清群（Sg）1。从办公楼收集的热水样本中嗜肺军团菌的检测频率更高，为 53%（16/30），浓度为 10GU/L（中位数）。办公楼的年龄不是污染的统计学显著预测因素，但面积（>100,000 平方英尺）是，P = <0.001。从住宅收集的热水样本中嗜肺军团菌的检测频率较低，为 36%（25/70），浓度为 100GU/L（中位数）。住宅的年龄是污染的显著预测因素，P = 0.009，但面积不是。水的二次消毒剂类型不会影响住宅中嗜肺军团菌的检测频率及其浓度，但会影响办公楼中的结果。嗜肺军团菌的最高检测频率出现在办公楼的 3 月至 8 月和住宅的 6 月至 11 月采集的样本中。
本研究表明，建筑环境会影响嗜肺军团菌的传输和归宿。住宅管道可能是热水环境上游来源的嗜肺军团菌暴露的潜在“渠道”。旧的和新建成的办公楼都有同等的嗜肺军团菌污染概率。在只包含商业功能的办公楼中进行与军团菌相关的修复工作可能不会显著改善社区的公共卫生状况。
