Regional Reference Laboratory of Clinical and Environmental Surveillance of Legionellosis, Department of Biomedical Science and Human Oncology, Section of Hygiene, University of Bari Aldo Moro, 70124 Bari, Italy.
Department of Biomedical Science and Human Oncology, University of Bari Aldo Moro, 70124 Bari, Italy.
Int J Environ Res Public Health. 2020 Mar 20;17(6):2077. doi: 10.3390/ijerph17062077.
Determination of concentrations in water networks is useful for predicting legionellosis risks. The standard culture technique using concentration with membranes filters is the most commonly used method for environmental surveillance of . The aim of this study was to verify whether filtration with different filter pore sizes (0.2 and 0.45 µm) according to (ISO) 11731:2017, followed by directly placing them on culture media, can influence detection. Three laboratories participated in an experimental study that tested a known suspension of () serogroup 1 (ATCC 33152) (approximate final cell density of 15 CFU/mL). (ATCC 11775) and (ATCC 25668) were included as control tests. The average (95% CI) percentage of recovery of was 65% using 0.45-µm filters and 15% using 0.2-µm filters ( < 0.0001). For control tests, the average (95% CI) percentage of recovery was higher with 0.45 vs. 0.2 µm filters: 97% vs. 64% for ( < 0.00001) and 105% vs. 97% ( = 0.0244) for . Our results showed that the 0.45-µm filters provided the greatest detection of . Because the current national guidelines leave the choice of membrane porosity to the operator, experimental studies are important for directing operators towards a conscious choice to standardize environmental surveillance methods.
确定水中的浓度对于预测军团病风险很有用。使用膜过滤器浓缩物的标准培养技术是环境监测的最常用方法。本研究旨在验证根据（ISO）11731：2017 用不同孔径（0.2 和 0.45 µm）的过滤器过滤，然后直接将其置于培养基上，是否会影响的检测。三个实验室参与了一项实验研究，该研究测试了已知的 1 群血清型 1（ATCC 33152）（约终细胞密度为 15 CFU/mL）悬液。将 （ATCC 11775）和 （ATCC 25668）作为对照试验。使用 0.45-µm 过滤器的 的平均（95%置信区间）回收率为 65%，而使用 0.2-µm 过滤器的回收率为 15%（<0.0001）。对于对照试验，使用 0.45 µm 过滤器的平均（95%置信区间）回收率高于 0.2 µm 过滤器：对于 （<0.00001）为 97% vs. 64%，对于 （=0.0244）为 105% vs. 97%。我们的结果表明，0.45-µm 过滤器可最大程度地检测到 。由于当前的国家指南允许操作人员选择膜的孔隙率，因此实验研究对于指导操作人员有意识地选择标准化环境监测方法很重要。
