Office of Research and Development, United States Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, OH 45268, United States.
Office of Research and Development, United States Environmental Protection Agency, 26 West Martin Luther King Drive, Cincinnati, OH 45268, United States.
Sci Total Environ. 2021 Jun 20;774:145727. doi: 10.1016/j.scitotenv.2021.145727. Epub 2021 Feb 9.
Levels of severe acute respiratory coronavirus type 2 (SARS CoV 2) RNA in wastewater could act as an effective means to monitor coronavirus disease 2019 (COVID-19) within communities. However, current methods used to detect SARS CoV 2 RNA in wastewater are limited in their ability to process sufficient volumes of source material, inhibiting our ability to assess viral load. Typically, viruses are concentrated from large liquid volumes using two stage concentration, primary and secondary. Here, we evaluated a dead-end hollow fiber ultrafilter (D-HFUF) for primary concentration, followed by the CP Select™ for secondary concentration from 2 L volumes of primary treated wastewater. Various amendments to each concentration procedure were investigated to optimally recover seeded OC43 (betacoronavirus) from wastewater. During primary concentration, the D-HFUF recovered 69 ± 18% (n = 29) of spiked OC43 from 2 L of wastewater. For secondary concentration, the CP Select™ system using the Wastewater Application settings was capable of processing 100 mL volumes of primary filter eluates in <25 min. A hand-driven syringe elution proved to be significantly superior (p = 0.0299) to the CP Select™ elution for recovering OC43 from filter eluates, 48 ± 2% compared to 31 ± 3%, respectively. For the complete method (primary and secondary concentration combined), the D-HFUF and CP select/syringe elution achieved overall 22 ± 4% recovery of spiked OC43 through (n = 8) replicate filters. Given the lack of available standardized methodology confounded by the inherent limitations of relying on viral RNA for wastewater surveillance of SARS CoV 2, it is important to acknowledge these challenges when interpreting this data to estimate community infection rates. However, the development of methods that can substantially increase sample volumes will likely allow for reporting of quantifiable viral data for wastewater surveillance, equipping public health officials with information necessary to better estimate community infection rates.
废水中严重急性呼吸冠状病毒 2 型 (SARS-CoV-2) RNA 的水平可作为监测社区内 2019 年冠状病毒病 (COVID-19) 的有效手段。然而，目前用于检测废水中 SARS-CoV-2 RNA 的方法在处理大量源材料的能力上存在局限性，限制了我们评估病毒载量的能力。通常，使用两级浓缩法（一级浓缩和二级浓缩）从大量液体体积中浓缩病毒。在这里，我们评估了用于一级浓缩的死端中空纤维超滤 (D-HFUF)，然后使用 CP Select™从 2 L 一级处理废水中进行二级浓缩。研究了每种浓缩程序的各种改进方法，以从废水中最佳回收接种的 OC43（β冠状病毒）。在一级浓缩过程中，D-HFUF 从 2 L 废水中回收了 69±18%（n=29）的刺 OC43。对于二级浓缩，使用废水应用设置的 CP Select™系统能够在<25 分钟内处理 100 mL 体积的一级过滤器洗脱液。手动驱动注射器洗脱在从过滤器洗脱液中回收 OC43 方面明显优于 CP Select™洗脱（p=0.0299），分别为 48±2%和 31±3%。对于完整方法（一级和二级浓缩相结合），D-HFUF 和 CP select/注射器洗脱通过（n=8）个重复过滤器总共实现了接种 OC43 的 22±4%的总体回收率。鉴于缺乏可用的标准化方法，并且依赖于病毒 RNA 进行 SARS-CoV-2 的废水监测存在固有局限性，因此在解释这些数据以估计社区感染率时，必须认识到这些挑战。然而，开发能够显著增加样品量的方法可能会允许报告可量化的病毒数据用于废水监测，使公共卫生官员能够获得必要的信息来更好地估计社区感染率。
