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
. 2021 May 17:12:664477.
doi: 10.3389/fmicb.2021.664477. eCollection 2021.

Viral RNA in City Wastewater as a Key Indicator of COVID-19 Recrudescence and Containment Measures Effectiveness

Nathalie Wurtz  1   2 , Alexandre Lacoste  3 , Priscilla Jardot  1 , Alain Delache  4 , Xavier Fontaine  3 , Maxime Verlande  3 , Alexandre Annessi  3 , Audrey Giraud-Gatineau  1   2 , Hervé Chaudet  2   5 , Pierre-Edouard Fournier  2   5 , Patrick Augier  3 , Bernard La Scola  1   2
Affiliations

Viral RNA in City Wastewater as a Key Indicator of COVID-19 Recrudescence and Containment Measures Effectiveness

Nathalie Wurtz et al. Front Microbiol. .

Abstract

In recent years, and more specifically at the beginning of the COVID-19 crisis, wastewater surveillance has been proposed as a tool to monitor the epidemiology of human viral infections. In the present work, from July to December 2020, the number of copies of SARS-CoV-2 RNA in Marseille's wastewater was correlated with the number of new positive cases diagnosed in our Institute of Infectious Disease, which tested about 20% of the city's population. Number of positive cases and number of copies of SARS-CoV-2 RNA in wastewater were significantly correlated (p = 0.013). During the great epidemic peak, from October to December 2020, the curves of virus in the sewers and the curves of positive diagnoses were perfectly superposed. During the summer period, the superposition of curves was less evident as subject to many confounding factors that were discussed. We also tried to correlate the effect of viral circulation in wastewater with containment measures, probably the most unbiased correlation on their potential inflection effect of epidemic curves. Not only is this correlation not obvious, but it also clearly appears that the drop in cases as well as the drop in the viral load in the sewers occur before the containment measures. In fact, this suggests that there are factors that initiate the end of the epidemic peak independently of the containment measure. These factors will therefore need to be explored more deeply in the future.

Keywords: COVID-19; RNA; SARS-CoV-2; sewers; wastewater.

PubMed Disclaimer

Conflict of interest statement

AD was employed by the company CAMGAU Consulting. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.

Figures

FIGURE 1
FIGURE 1
Wastewater networks in Marseille. The separate network (red lines) drains the major surface part of Marseille wastewater. The combined network (green lines), that contains a mixture of rainwater and wastewater, drains the city center. The blue circle represents the sampling point.
FIGURE 2
FIGURE 2
Variations in mean outdoor temperature (dark gray) and rain fall (light gray) during the period of study (from July 1 to December 15). Copy number of SARS-CoV-2 in RU (green) and RS (red) wastewater networks were represented.
FIGURE 3
FIGURE 3
Correlation of SARS-CoV-2 Marseille new positives cases (blue curve) and copy number of SARS-CoV-2 in RU + RS wastewater networks (orange curve). Eight-days moving average was represented. The measures implemented by government were positioned at the day of application. In gray, the period where efficiency of the measures can be observed.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

References

    1. Agrawal S., Orschler L., Lackner S. (2021). Long-term monitoring of SARS-CoV-2 RNA in wastewater of the frankfurt metropolitan area in southern germany. Sci. Rep. 11:5372. 10.1038/s41598-021-84914-2 - DOI - PMC - PubMed
    1. Ahmed W., Angel N., Edson J., Bibby K., Bivins A., O’Brien J. W., et al. (2020). 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. 728:138764. 10.1016/j.scitotenv.2020.138764 - DOI - PMC - PubMed
    1. Albastaki A., Naji M., Lootah R., Almeheiri R., Almulla H., Almarri I., et al. (2020). First confirmed detection of SARS-COV-2 in untreated municipal and aircraft wastewater in Dubai, UAE: the use of wastewater based epidemiology as an early warning tool to monitor the prevalence of COVID-19. Sci Total Environ. 760:143350. 10.1016/j.scitotenv.2020.143350 - DOI - PMC - PubMed
    1. Alpaslan Kocamemi B., Kurt H., Hacioglu S., Yarali C., Saatci A. M., Pakdemirli B. (2020). First data-set on SARS-CoV-2 detection for istanbul wastewaters in turkey. [preprint] 10.1101/2020.05.03.20089417 - DOI
    1. Al-Tawfiq J. A. (2020). Asymptomatic coronavirus infection: MERS-CoV and SARS-CoV-2 (COVID-19). Travel Med. Infect. Dis. 35:101608. 10.1016/j.tmaid.2020.101608 - DOI - PMC - PubMed