COVID-19 virus levels are rising at wastewater treatment plants in the two largest metropolitan areas in North Carolina, indicating that case counts could be on the rise.
According to the N.C. Department of Health and Human Services, rising levels of COVID-19 virus particles in wastewater can be an early sign of community spread.
At the Mallard Creek plant in Charlotte, an average of 11 million viral gene copies per person were recorded on May 23, according to the most recent data available from NCDHHS. By July 25, that number climbed to 32 million.
Viral gene copies at a plant in Raleigh rose to 42 million near the end of July, up from 2 million just seven weeks prior.
COVID-19 wastewater levels have remained relatively flat at the other plants in both areas, data show.
COVID-19 in Mecklenburg, Wake counties
As COVID-19 wastewater levels rise in some parts of the state, so have the number of hospitalizations related to the virus.
From July 15-22, there were 33 COVID-related hospitalizations reported in Mecklenburg County, a 32% increase from the previous week, according to the most recent data from the Centers for Disease Control and Prevention.
Wake County saw a similar increase, with 21 hospitalizations reported during the same week.
Wastewater data usually corresponds with the number of cases reported in a particular area, and people should be cautious despite the low number of hospitalizations compared to previous months, Virginia Guidry, the branch head for occupational and environmental epidemiology at NCDHHS, told The Charlotte Observer last June.
“We’re pretty confident in our wastewater data as a way to measure what’s going on in the community,” Guidry said. “And it captures both symptomatic and asymptomatic folks, regardless of whether they get tested, and that is one the real advantages of wastewater monitoring.”
How can wastewater help detect COVID spread?
Wastewater can be an important tool for scientists who study SARS-CoV-2, according to the CDC. Here’s how:
-
Wastewater data showing the percent change in virus levels can be used with other data, like the overall levels of the virus in the water and historical wastewater for a particular location. Levels of the virus in wastewater could be an indicator of how well prevention strategies are working.
-
Small changes in the level of virus in wastewater can be an early signal that the number of people with COVID-19 in a community is rising or falling.
-
State and local health officials can use wastewater data to predict trends in COVID-19 transmission and respond accordingly.
