Quantitative association of SARS-CoV-2 in wastewater and clinically confirmed cases in different areas of the Tokyo 2020 Olympic and Paralympic Village

Masaaki Kitajima; Michio Murakami; Hiroki Ando; Syun-Suke Kadoya; Ryo Iwamoto; Tomohiro Kuroita; Kiyoshi Yamaguchi; Hiroyuki Kobayashi; Satoshi Okabe; Hiroyuki Katayama; Seiya Imoto

doi:10.1016/j.scitotenv.2024.178209

Quantitative association of SARS-CoV-2 in wastewater and clinically confirmed cases in different areas of the Tokyo 2020 Olympic and Paralympic Village

Sci Total Environ. 2025 Jan 6:960:178209. doi: 10.1016/j.scitotenv.2024.178209. Online ahead of print.

Authors

Affiliations

¹ Research Center for Water Environment Technology, Graduate School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan. Electronic address: [email protected].
² Center for Infectious Disease Education and Research, Osaka University, 2-8 Yamadaoka, Suita, Osaka 565-0871, Japan.
³ Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan; Mel and Enid Zuckerman College of Public Health, University of Arizona, Tucson, AZ 85724, United States.
⁴ Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
⁵ Shionogi & Co. Ltd., 1-8 Doshomachi 3-Chome, Chuo-ku, Osaka 541-0045, Japan; AdvanSentinel Inc., 1-8 Doshomachi 3-Chome, Chuo-ku, Osaka 541-0045, Japan.
⁶ Division of Clinical Genome Research, The Institute of Medical Science, The University of Tokyo, 4-6-1, Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.
⁷ Shionogi & Co. Ltd., 1-8 Doshomachi 3-Chome, Chuo-ku, Osaka 541-0045, Japan.
⁸ Division of Environmental Engineering, Faculty of Engineering, Hokkaido University, North 13 West 8, Kita-ku, Sapporo, Hokkaido 060-8628, Japan.
⁹ Research Center for Water Environment Technology, Graduate School of Engineering, The University of Tokyo, 2-11-16 Yayoi, Bunkyo-ku, Tokyo 113-0032, Japan; Department of Urban Engineering, Graduate School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656, Japan.
¹⁰ Human Genome Center, The Institute of Medical Science, The University of Tokyo, 4-6-1 Shirokanedai, Minato-ku, Tokyo 108-8639, Japan.

PMID: 39765173
DOI: 10.1016/j.scitotenv.2024.178209

Abstract

International mass gathering events, such as the Olympic and Paralympic Games, face the risk of cross-border transmission of infectious diseases. We previously reported that wastewater-based epidemiology (WBE), which has attracted attention as a COVID-19 surveillance tool, was implemented in the Tokyo 2020 Olympic and Paralympic Village to gain a comprehensive understanding of COVID-19 incidence in the village. In the present study, we explored the quantitative association of wastewater viral load and clinically confirmed cases in various areas of the village. From July 14 through September 8, 2021, 360 passive samples and 329 grab samples were collected from seven distinct areas within the village through manholes and examined for SARS-CoV-2 RNA by the Efficient and Practical virus Identification System with Enhanced Sensitivity (EPISENS) methods. The detection rates of SARS-CoV-2 RNA in passive and grab samples showed a significant association (P < 0.001, φ = 0.32, chi-square test), with passive sampling showing higher positive rate. Based on the Receiver Operating Characteristic (ROC) curve analysis on the wastewater viral load and clinically confirmed cases, the most sensitive cutoff point was judged to be the limit of quantification (LOQ) for the passive three-day samples. Under this optimal condition, the sensitivity and specificity were 0.78 and 0.40, respectively. The present study demonstrated the effectiveness of passive sampling for building-level wastewater surveillance based on the quantitative analysis of wastewater viral load and reported cases. Wastewater surveillance can be a powerful tool to monitor the incidence of infectious diseases among temporary residents, such as tourists and participants in international mass gathering events, provided that proper analytical methods and quantitative cutoff point are employed.

Keywords: COVID-19; Mass gathering; Passive sampling; Receiver operating characteristic curve analysis; Wastewater surveillance; Wastewater-based epidemiology.