Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2022 Dec 20:853:158458.
doi: 10.1016/j.scitotenv.2022.158458. Epub 2022 Sep 6.

Understanding the dynamic relation between wastewater SARS-CoV-2 signal and clinical metrics throughout the pandemic

Nada Hegazy  1 , Aaron Cowan  1 , Patrick M D'Aoust  1 , Élisabeth Mercier  1 , Syeda Tasneem Towhid  1 , Jian-Jun Jia  1 , Shen Wan  1 , Zhihao Zhang  1 , Md Pervez Kabir  1 , Wanting Fang  1 , Tyson E Graber  2 , Alex E MacKenzie  2 , Stéphanie Guilherme  1 , Robert Delatolla  3
Affiliations

Understanding the dynamic relation between wastewater SARS-CoV-2 signal and clinical metrics throughout the pandemic

Nada Hegazy et al. Sci Total Environ. .

Abstract

Wastewater surveillance (WWS) of SARS-CoV-2 was proven to be a reliable and complementary tool for population-wide monitoring of COVID-19 disease incidence but was not as rigorously explored as an indicator for disease burden throughout the pandemic. Prior to global mass immunization campaigns and during the spread of the wildtype COVID-19 and the Alpha variant of concern (VOC), viral measurement of SARS-CoV-2 in wastewater was a leading indicator for both COVID-19 incidence and disease burden in communities. As the two-dose vaccination rates escalated during the spread of the Delta VOC in Jul. 2021 through Dec. 2021, relations weakened between wastewater signal and community COVID-19 disease incidence and maintained a strong relationship with clinical metrics indicative of disease burden (new hospital admissions, ICU admissions, and deaths). Further, with the onset of the vaccine-resistant Omicron BA.1 VOC in Dec. 2021 through Mar. 2022, wastewater again became a strong indicator of both disease incidence and burden during a period of limited natural immunization (no recent infection), vaccine escape, and waned vaccine effectiveness. Lastly, with the populations regaining enhanced natural and vaccination immunization shortly prior to the onset of the Omicron BA.2 VOC in mid-Mar 2022, wastewater is shown to be a strong indicator for both disease incidence and burden. Hospitalization-to-wastewater ratio is further shown to be a good indicator of VOC virulence when widespread clinical testing is limited. In the future, WWS is expected to show moderate indication of incidence and strong indication of disease burden in the community during future potential seasonal vaccination campaigns.

Keywords: Deaths; Hospital admissions; Laboratory positive cases; Vaccination; WWS.

PubMed Disclaimer

Conflict of interest statement

Declaration of competing interest The authors declare that no competing financial interests or personal relationships influenced the work reported in this manuscript.

Figures

Unlabelled Image
Graphical abstract
Fig. 1
Fig. 1
Relation between SARS-CoV-2 wastewater signal (advanced by respective “△t” time lag on the x-axis) and A) clinical COVID-19 positive cases/100,000 inhabitants in Ottawa and B) clinical COVID-19 positive cases/100,000 inhabitants in Hamilton, C) hospital admissions/100,000 inhabitants in Ottawa and D) hospitalization admissions/100,000 inhabitants in Hamilton, E) ICU admissions/100,000 inhabitants in Ottawa and F) ICU admissions/100,000 inhabitants in Hamilton, and G) COVID-19 caused deaths/100,000 inhabitants in Ottawa, and H) COVID-19 caused deaths/100,000 inhabitants in Hamilton from Apr. 8th, 2020 to May. 26th, 2022. *Laboratory positive cases in Ottawa and Hamilton are underreported due to updated PCR eligibility in Ontario as of Dec. 31st, 2021.
Fig. 2
Fig. 2
Relation between SARS-CoV-2 wastewater signal (advanced by respective “△t” time lag on the x-axis) and A) clinical COVID-19 positive cases/100,000 inhabitants in Ottawa and B) clinical COVID-19 positive cases/100,000 inhabitants in Hamilton, C) hospital admissions/100,000 inhabitants in Ottawa and D) hospitalization admissions/100,000 inhabitants in Hamilton, E) ICU admissions/100,000 inhabitants in Ottawa and F) ICU admissions/100,000 inhabitants in Hamilton, and G) COVID-19-caused deaths/100,000 inhabitants in Ottawa, and H) COVID-19 caused deaths/100,000 inhabitants in Hamilton post 70 % vaccination of total population and prior to Omicron surge (Aug. 30th, 2021–Nov. 27th, 2021, in Ottawa, and Oct 9th, 2021–Nov. 27th, 2021, in Hamilton).
Fig. 3
Fig. 3
Relation between SARS-CoV-2 wastewater signal (advanced by respective “△t” time lag on the x-axis) and A) laboratory COVID-19 positive cases/100,000 inhabitants in Ottawa and B) laboratory COVID-19 positive cases/100,000 inhabitants in Hamilton, C) hospital admissions/100,000 inhabitants in Ottawa and D) hospitalization admissions/100,000 inhabitants in Hamilton, E) ICU admissions/100,000 inhabitants in Ottawa and F) ICU admissions/100,000 inhabitants in Hamilton, and G) COVID-19 caused deaths/100,000 inhabitants in Ottawa, and H) COVID-19 caused deaths/100,000 inhabitants in Hamilton during the Omicron BA.1 (B.1.1.529.1) surge (Nov. 28th, 2021, to Feb. 22nd, 2022). *Laboratory positive cases in Ottawa and Hamilton are underreported due to updated PCR eligibility in Ontario as of Dec. 31st, 2021.
Fig. 4
Fig. 4
Relation between SARS-CoV-2 wastewater signal (advanced by respective “△t” time lag on the x-axis and A) laboratory COVID-19 positive cases/100,000 inhabitants in Ottawa and B) laboratory COVID-19 positive cases/100,000 inhabitants in Hamilton, C) hospital admissions/100,000 inhabitants in Ottawa and D) hospitalization admissions/100,000 inhabitants in Hamilton, E) ICU admissions/100,000 inhabitants in Ottawa and F) ICU admissions/100,000 inhabitants in Hamilton, and G) COVID-19 caused deaths/100,000 inhabitants in Ottawa, and H) COVID-19 caused deaths/100,000 inhabitants in Hamilton during the Omicron BA.2 (B.1.1.529.2) surge post removal of protection/face masking protection (Mar. 21th, 2022 to May 26th, 2022). *Laboratory positive cases in Ottawa and Hamilton are underreported due to updated PCR eligibility in Ontario as of Dec. 31st, 2021.
Fig. 5
Fig. 5
Comparison of hospitalization to wastewater ratio amplitude during the onset of the B.1.1.7 (Alpha), B.1.617 (Delta), B.1.1.529.1 (Omicron BA.1), and B.1.1.529.2 (Omicron BA.2 – post facemask removal) VOCs in Ottawa and Hamilton.
See this image and copyright information in PMC

References

    1. Abu-Raddad L.J., Chemaitelly H., Bertollini R. Severity of SARS-CoV-2 reinfections as compared with primary infections. N. Engl. J. Med. 2021;385:2487–2489. doi: 10.1056/NEJMc2108120. - DOI - PMC - PubMed
    1. Ahmed W., Angel N., Edson J., Bibby K., Bivins A., O’Brien J.W., Choi P.M., Kitajima M., Simpson S.L., Li J., Tscharke B., Verhagen R., Smith W.J.M., Zaugg J., Dierens L., Hugenholtz P., Thomas K.V., Mueller J.F. First confirmed detection of SARS-CoV-2 in untreated wastewater in Australia: a proof of concept for the wastewater surveillance of COVID-19 in the community. Sci. Total Environ. 2020;728 doi: 10.1016/j.scitotenv.2020.138764. - DOI - PMC - PubMed
    1. Andrejko K.L., Pry J.M., Myers J.F., Fukui N., DeGuzman J.L., Openshaw J., Watt J.P., Lewnard J.A., Jain S., Abdulrahim Y., Barbaduomo C.M., Bermejo M.I., Cheunkarndee J., Cornejo A.F., Corredor S., Dabbagh N., Dong Z.N., Dyke A., Fang A.T., Felipe D., Frost P.M., Ho T., Javadi M.H., Kaur A., Lam A., Li S.S., Miller M., Ni J., Park H., Poindexter D.J., Samani H., Saretha S., Spencer M., Spinosa M.M., Tran V.H., Walas N., Wan C., Xavier E., Team C.C.-19 C.-C.S, Team C.C.-19 C.-C.S Effectiveness of face mask or respirator use in indoor public settings for prevention of SARS-CoV-2 infection — California, February–December 2021. Morb. Mortal. Wkly Rep. 2022;71:212. doi: 10.15585/MMWR.MM7106E1. - DOI - PMC - PubMed
    1. Andrews N., Stowe J., Kirsebom F., Toffa S., Rickeard T., Gallagher E., Gower C., Kall M., Groves N., O’Connell A.-M., Simons D., Blomquist P.B., Zaidi A., Nash S., Aziz N.I.B.A., Thelwall S., Dabrera G., Myers R., Amirthalingam G., Gharbia S., Barrett J.C., Elson R., Ladhani S.N., Ferguson N., Zambon M., Campbell C.N.J., Brown K., Hopkins S., Chand M., Ramsay M., Bernal J.L. Covid-19 vaccine effectiveness against the omicron (B.1.1.529) variant. N. Engl. J. Med. 2022;386:1532–1546. doi: 10.1056/NEJMOA2119451. - DOI - PMC - PubMed
    1. Asghar H., Diop O.M., Weldegebriel G., Malik F., Shetty S., El Bassioni L., Akande A.O., Al Maamoun E., Zaidi S., Adeniji A.J., Burns C.C., Deshpande J., Oberste M.S., Lowther S.A. Environmental surveillance for polioviruses in the global polio eradication initiative. J. Infect. Dis. 2014;210:S294–S303. doi: 10.1093/INFDIS/JIU384. - DOI - PMC - PubMed

Supplementary concepts