COVID

Is the current COVID surge peaking? New wastewater data shows a turnaround

Levels of the virus have been rising since March, but some are optimistic about a sustained decrease.

Wastewater from 43 communities is analyzed at a plant on Deer Island. David L Ryan/Globe Staff

May 24, 2022

Researchers are optimistic that new data from wastewater shows that the current COVID-19 surge could soon come to an end. The information was posted Monday by the Massachusetts Water Resources Authority. It shows decreasing levels of SARS-CoV-2, the virus that causes COVID-19.

Wastewater is analyzed by the MWRA at the organization’s Deer Island Treatment Plant. Data from this analysis is split up into two groups: the southern and northern regions of the MWRA system. The recent decrease is especially prominent in wastewater collected from the southern region, according to Bill Hanage, an associate professor at Harvard’s T.H. Chan School of Public Health.

“Something has definitely changed in the Southern system,” Hanage wrote on Twitter Tuesday.

However, he warned that this dip could prove unsustainable due to the numerous transmission opportunities at this time of year.

The MWRA’s southern region, where the decrease is most pronounced, includes communities like Framingham, Quincy, and a large portion of Brookline. The full map can be found on the organization’s website.

The recent data indicates roughly two days of decreasing COVID levels. Since early March, these numbers have been rising steadily.

Boston Wastewater watch – something has definitely changed in the Southern system (a similar though less pronounced drop is visible in the north). It may not be sustained, given many opportunities for transmission during graduation season, but it is welcome pic.twitter.com/jQ9eR307Xp
— Bill Hanage (@BillHanage) May 24, 2022

Wastewater surveillance is a powerful tool for predicting future COVID trends. This is because those infected with the virus can shed it in their feces, even if they don’t have symptoms, according to the CDC. The virus can then be detected in wastewater, serving as an early warning sign for further outbreaks in particular locations.

Wastewater analysis could be even more essential at this stage of the pandemic, when more people than ever are relying on rapid at-home tests. Since these results are less frequently reported to public health organizations, wastewater data is crucial.