NC Monitoring Wastewater Systems For COVID-19 Virus Clues

NORTH CAROLINA — As coronavirus testing begins to wane, North Carolina public health officials' efforts to track COVID-19 in the state have now turning to poop. But in a productive way. The North Carolina Department of Health and Human Services is testing wastewater samples at 11 treatment facilities around the state in a bid to measure shed viral particles found in the feces of those infected with COVID-19.

Data from the monitoring program, which began in January, is now available on the NC COVID-19 Dashboard.

As of May 11, for example, the state agency reported that COVID-19 virus in wastewater samples in Charlotte had plateaued.

"Wastewater monitoring is a new tool that will help us track the spread of COVID-19 in participating communities even as fewer people are being tested," State Epidemiologist Dr. Zack Moore said in a statement. "This can be an early warning system and allow health officials to take actions to stop the spread if trends are increasing."

The North Carolina Wastewater Monitoring Network program is a collaboration between eight public health departments, the University of North Carolina and 11 wastewater utility facilities located in Charlotte, Greenville, Newport, Pittsboro, Raleigh, Chapel Hill-Carrboro, New Hanover County, South Durham, the Town of Beaufort and Wilmington City.

"People who are infected with COVID-19 shed viral particles in their feces," DHHS said. "These viral particles are no longer infectious in wastewater but can be measured if enough people are infected."

Public health officials are able to track COVID-19 trends in a community by taking a sample, which detects virus shed by both those were are asymptomatic and symptomatic.

"This can be important as asymptomatic people are rarely tested and the CDC estimates that 50 percent of COVID-19 transmission is caused by people without symptoms," DHHS said.

Preliminary data trends from the program show results that are similar for individual test results in the communities, DHHS said. However, the method of monitoring community spread trends comes with limitations. About 40 percent of North Carolinians use septic tanks for their wastewater.

Should the data indicate a spike in infections, DHHS would notify the wastewater treatment plant and local health officials, who could implement the following:

• Mobilize or increase pop-up testing.
• Increase public health communications on the importance of masking, handwashing, social distancing and avoiding large crowds in enclosed spaces.
• Alert local hospitals, clinics and other health care providers about a potential increase in cases.
• Provide recommendations to community leaders or implement restrictions like limiting indoor gatherings and reducing business capacity.
• Take steps to increase vaccination in the community.

As of Friday, May 21, nearly 996,000 cases of COVID-19 had been reported in North Carolina and at least 12,958 deaths in the state were attributed to the virus, DHHS said.