Abstract:
SARS-CoV-2 RNA loads can be detected in the excreta of individuals with COVID-19 and have demonstrated positive correlations with clinical infection trends. Consequently, wastewater-based epidemiology (WBE) approaches have been implemented globally as a public health surveillance tool to monitor community-level prevalence of infections. The majority of wastewater specimens are gathered as either composite samples via automatic samplers (autosamplers) or grab samples. However, autosamplers are expensive and can be challenging to maintain in cold weather, while grab samples are particularly susceptible to temporal variation when sampling sewage directly from complex matrices outside residential buildings. Passive sampling can provide an affordable, practical, and scalable sampling system while maintaining a reproducible SARS-CoV-2 signal. In this regard, we deployed tampons as passive samplers outside of a COVID-19 isolation unit (a segregated residence hall) at a university campus from 1 February 2021-21 May 2021. Samples (n = 64) were collected 3-5 times weekly and remained within the sewer for a median duration of 24 h. SARS-CoV-2 RNA was quantified using reverse-transcription quantitative polymerase chain reaction (RT-qPCR) targeting the N1 and N2 gene fragments. We quantified the mean viral load captured per individual and the association between the daily viral load and total persons, adjusting for covariates using multivariable models to provide a baseline estimate of viral shedding. Samples were processed through two distinct laboratory pipelines on campus, yielding highly correlated N2 concentrations. Data obtained here highlight the success of passive sampling utilizing tampons to capture SARS-CoV-2 in wastewater coming from a COVID-19 isolation residence, indicating that this method can help inform building-level public health responses.
摘要:
在COVID-19患者的排泄物中可以检测到SARS-CoV-2RNA负荷,并已证明与临床感染趋势呈正相关。因此,基于废水的流行病学(WBE)方法已在全球范围内实施,作为一种公共卫生监测工具,以监测社区一级的感染流行率。大多数废水标本通过自动采样器(自动进样器)或抓取样品作为复合样品收集。然而,自动进样器价格昂贵,在寒冷的天气中维护起来很困难,而当直接从住宅建筑外的复杂基质中采样污水时,抓取样本特别容易受到时间变化的影响。被动采样可以提供一个负担得起的,实用,和可扩展的采样系统,同时保持可重现的SARS-CoV-2信号。在这方面,从2021年2月1日至2021年5月21日,我们在大学校园的COVID-19隔离单元(隔离宿舍)外部署了卫生棉条作为被动采样器。每周收集3-5次样品(n=64),并保持在下水道中24小时的中值持续时间。使用靶向N1和N2基因片段的逆转录定量聚合酶链反应(RT-qPCR)定量SARS-CoV-2RNA。我们量化了每个人捕获的平均病毒载量以及每日病毒载量与总人数之间的关联,使用多变量模型调整协变量,以提供病毒脱落的基线估计。样本是通过校园内两个不同的实验室管道处理的,产生高度相关的N2浓度。这里获得的数据突出了利用卫生棉条被动采样成功捕获来自COVID-19隔离住所的废水中的SARS-CoV-2,表明这种方法可以帮助告知建筑物级别的公共卫生响应。