Near full-automation of COPMAN using a LabDroid enables high-throughput and sensitive detection of SARS-CoV-2 RNA in wastewater as a leading indicator

https://doi.org/10.1016/j.scitotenv.2023.163454Get rights and content
Under a Creative Commons license
open access

Highlights

  • COPMAN is a detection method for viral RNA in 8–10 mL of wastewater.

  • Near-full automation was achieved by combining COPMAN with a versatile robot.

  • A linear correlation between detected SARS-CoV-2 and reported cases was observed.

  • COPMAN-detected SARS-CoV-2 could be a leading indicator of reported cases.

Abstract

Wastewater-based epidemiology (WBE) is a promising tool to efficiently monitor COVID-19 prevalence in a community. For WBE community surveillance, automation of the viral RNA detection process is ideal. In the present study, we achieved near full-automation of a previously established method, COPMAN (COagulation and Proteolysis method using MAgnetic beads for detection of Nucleic acids in wastewater), which was then applied to detect SARS-CoV-2 in wastewater for half a year. The automation line employed the Maholo LabDroid and an automated-pipetting device to achieve a high-throughput sample-processing capability of 576 samples per week. SARS-CoV-2 RNA was quantified with the automated COPMAN using samples collected from two wastewater treatment plants in the Sagami River basin in Japan between 1 November 2021 and 24 May 2022, when the numbers of daily reported COVID-19 cases ranged from 0 to 130.3 per 100,000 inhabitants. The automated COPMAN detected SARS-CoV-2 RNA from 81 out of 132 samples at concentrations of up to 2.8 × 105 copies/L. These concentrations showed direct correlations with subsequently reported clinical cases (5–13 days later), as determined by Pearson's and Spearman's cross-correlation analyses. To compare the results, we also conducted testing with the EPISENS-S (Efficient and Practical virus Identification System with ENhanced Sensitivity for Solids, Ando et al., 2022), a previously reported detection method. SARS-CoV-2 RNA detected with EPISENS-S correlated with clinical cases only when using Spearman's method. Our automated COPMAN was shown to be an efficient method for timely and large-scale monitoring of viral RNA, making WBE more feasible for community surveillance.

Abbreviations1

COPMAN
COagulation and Proteolysis method using MAgnetic beads for detection of Nucleic acids in wastewater
EPISENS-S
Efficient and Practical virus Identification System with ENhanced Sensitivity for Solids
WBE
wastewater-based epidemiology
COVID-19
coronavirus disease 2019
SARS-CoV-2
severe acute respiratory syndrome coronavirus 2
PMMoV
pepper mild mottle virus
WWTP
wastewater treatment plant

Keywords

Wastewater-based epidemiology
COVID-19
Sewage
Environmental surveillance
Automation
Maholo LabDroid

Data availability

The authors do not have permission to share data.

Cited by (0)

1

We use the “COPMAN” word as the workflow which consists of RNA extraction from wastewater and RT-qPCR detection.