Wayne State University SARS-CoV-2 monitoring in the City of Detroit, Public Data Page
Jeffrey L. Ram (Department of Physiology) and
William Shuster (Department of Civil and Environmental Engineering)
Lance Gable (School of Law)
For a summary of the objectives and methods of the project, see the
SARS-CoV-2-Wastewater Monitoring Project Summary
The above graphs cover the period of November 2021 until July 2024 and report the integrated result of sampling 22 sewersheds in the city of Detroit. The sewersheds are located all over the city, including southwest, northwest, northeast, south-central (e.g., near Belle Isle), and in the center of the city, including the DMC area and Wayne State. The sewersheds vary in size from a single building (a Wayne State dormitory) to as large as most of a ZIP Code area. The graphs show the average trends of SARS-CoV-2 levels in the community on the green graph (as the % of sites that are above 1,000 copies/100 mL wastewater) and the blue line on the green graph (the number of sites out of 22 that exceeded 5,000 copies/100 mL). The orange graph shows the average COVID-19 virus (SARS-CoV-2) markers calculated as the geometric mean. The purpose of the graphs are to show overall trends of total wastewater COVID-19 virus (SARS-CoV-2) levels in Detroit, and not to identify particular locations (therefore, no site names or maps are provided). A general view from these data is that SARS-CoV-2 viral markers in wastewater in Detroit generally decreased from the end of February 2023 until the end of June 2023 and then beginning around the Fourth of July, 2023 SARS-CoV-2 had two outbreak "waves," one peaking in early September, 2023 and an outbreak that peaked in January 2024. Will the same pattern be repeated in 2024? The most recent outbreak, reflected in wastewater measurements that peaked in January, 2024, trended downward after January with occasion sporadic upticks, until the end of June 2024. However, at the beginning of July 2024 the percentage of sites positive for SARS-CoV-2 (Green graph) began to rise and is currently (since the end of July 2024) over 50% of sites positive for the virus. It certainly seems like a new outbreak of COVID-19 is occurring in Detroit, according to these wastewater data. New COVID-19 infections are occurring in Detroit. Recommendations would be to make sure your vaccinations are up to date and to wear masks in crowded indoor spaces. Your odds of encountering an infected person are much higher than they were two months ago.
Historical interpretation of the graphs: The period before the earliest date shown in this graph (summer 2021) had had very low levels of virus in wastewater and low numbers of cases in Michigan and Detroit. At the beginning of this graph (November 2021), virus levels began to rise, most likely due to the Delta variant of SARS-CoV-2 ), rising to a peak at the beginning of November 2021, and then subsided somewhat until December, 2021. The rapid rise in virus levels at the end of December 2021 and continuing through January 2022 was the Omicron outbreak. While the Omicron outbreak subsided through February and the beginning of March 2022, the viral levels surged again after April 2022, said to correspond to various variants of the Omicron strain. Outbreaks peaked again in May 2022 and had sporadic increases during summer, 2022, in contrast to the much lower levels that had occurred in Summer 2021. The rise in the curve in December 2022 and 2023 seems to follow an "annual" pattern of increasing COVID-19 infections following Thanksgiving. The fall in marker levels in February through April 2023 follows the pattern observed in February and March 2022; however, unlike 2022, the low levels measured throughout Spring 2023 were sustained through July 2023. Since July, 2023, we have had two major waves of infections in the city, the first peaking in early September and the second peaking the last week in December.
Historical interpretation of the graphs: The period before the earliest date shown in this graph (summer 2021) had had very low levels of virus in wastewater and low numbers of cases in Michigan and Detroit. At the beginning of this graph (November 2021), virus levels began to rise, most likely due to the Delta variant of SARS-CoV-2 ), rising to a peak at the beginning of November 2021, and then subsided somewhat until December, 2021. The rapid rise in virus levels at the end of December 2021 and continuing through January 2022 was the Omicron outbreak. While the Omicron outbreak subsided through February and the beginning of March 2022, the viral levels surged again after April 2022, said to correspond to various variants of the Omicron strain. Outbreaks peaked again in May 2022 and had sporadic increases during summer, 2022, in contrast to the much lower levels that had occurred in Summer 2021. The rise in the curve in December 2022 and 2023 seems to follow an "annual" pattern of increasing COVID-19 infections following Thanksgiving. The fall in marker levels in February through April 2023 follows the pattern observed in February and March 2022; however, unlike 2022, the low levels measured throughout Spring 2023 were sustained through July 2023. Since July, 2023, we have had two major waves of infections in the city, the first peaking in early September and the second peaking the last week in December.
The graph starts after October 2021, the date at which we began to use a new technique to isolate the SARS-CoV-2 markers from wastewater. This new technique, using a Perkin-Elmer Chemagic 360 Nucleic Acid Purification instrument, is able to extract the viral markers more efficiently than previous measurements which used a PEG/NaCl/Qiagen extraction technique. Recent analysis indicate that levels detected using the Chemagic 360 are about 5 times higher when compared to same samples extracted by the previous (PEG/NaCl/Qiagen) technique (West et al., 2022, https://www.sciencedirect.com/science/article/pii/S0048969722046459?via%3Dihub) . At some sites we are collecting wastewater by absorbant swabs retrieved after several hours of immersion in the sewer flow, a technique that we've found to give a further 3 - 10-fold increase in sensitivity of detection (West et al. 2023., https://www.sciencedirect.com/science/article/pii/S0048969723028012).
Data on case rates at Michigan long-term-care facilities can be found at a State of Michigan site.