基于废水的流行病学(WBE)已经成为一种识别、locate,并管理COVID-19的爆发,从而有可能防止病例激增,这压倒了本地到全球医疗保健网络。WBE方法基于对城市废水进行SARS-CoV-2病毒分子标记的分析。从市政废水中纯化病毒RNA的标准方法通常很耗时,并且需要处理大量的废水。对吞吐量产生负面影响,及时报告,和安全。我们在这里演示一个自动化的,更快的系统从较小体积的废水中纯化病毒RNA,但对SARS-CoV-2标记的检测灵敏度提高。通过与密歇根州规定的用于SARS-CoV-2废水监测的PEG/NaCl/Qiagen方法进行比较,我们记录了这种新方法的有效性,并展示了其在底特律几个污水处理厂的应用。具体来说,与PEG/NaCl/Qiagen方法相比,使用PerkinElmerChemagic™360的病毒RNA纯化降低了处理时间,将所需的废水量减少了十倍,每μl最终洗脱产物分离的RNA量增加约五倍,并有效地从大多数污水样本中去除ddPCR抑制剂。为了检测病毒可检测性边界线上的标记,我们发现使用Chemagic™360能够测量大量样品中的病毒标志物,其中PEG/NaCl/Qiagen方法的结果低于可检测水平。病毒标记物的可检测性的提高对于在爆发开始时向公共卫生当局发出预警可能尤为重要。适用于底特律的下水道,该技术可以更灵敏地检测SARS-CoV-2标记,废水信号与下水道中的COVID-19病例之间具有良好的相关性。我们还讨论了几种自动化RNA纯化系统的优缺点,Promega制造的,PerkinElmer,和ThermoFisher.
Wastewater based epidemiology (WBE) has emerged as a strategy to identify, locate, and manage outbreaks of COVID-19, and thereby possibly prevent surges in cases, which overwhelm local to global health care networks. The WBE process is based on assaying municipal wastewater for molecular markers of the SARS-CoV-2 virus. Standard processes for purifying viral RNA from municipal wastewater are often time-consuming and require the handling of large quantities of wastewater, negatively affecting throughput, timely reporting, and safety. We demonstrate here an automated, faster system to purify viral RNA from smaller volumes of wastewater but with increased sensitivity for detection of SARS-CoV-2 markers. We document the effectiveness of this new approach by way of comparison to the PEG/NaCl/Qiagen method prescribed by the State of Michigan for SARS-CoV-2 wastewater monitoring and show its application to several Detroit sewersheds. Specifically, compared to the PEG/NaCl/Qiagen method, viral RNA purification using the PerkinElmer Chemagic™ 360 lowered handling time, decreased the amount of wastewater required by ten-fold, increased the amount of RNA isolated per μl of final elution product by approximately five-fold, and effectively removed ddPCR inhibitors from most sewershed samples. For detection of markers on the borderline of viral detectability, we found that use of the Chemagic™ 360 enabled the measurement of viral markers in a significant number of samples for which the result with the PEG/NaCl/Qiagen method was below the level of detectability. The improvement in detectability of the viral markers might be particularly important for early warning to public health authorities at the beginning of an outbreak. Applied to sewersheds in Detroit, the technique enabled more sensitive detection of SARS-CoV-2 markers with good correlation between wastewater signals and COVID-19 cases in the sewersheds. We also discuss advantages and disadvantages of several automated RNA purification systems, made by Promega, PerkinElmer, and ThermoFisher.