Analyzing human waste could prove to be a valuable early detection tool to identify increases in COVID-19 cases or see where new hot spots might emerge.

An analysis of solid waste from a wastewater treatment plant in New Haven by researchers at Yale University and the Connecticut Agricultural Experiment Station from March 19 until May 1 showed that the amount of viral genetic material found in the waste corresponded with the COVID-19 infection rate in New Haven County.

In addition to providing trend data, the study also showed that the amount of virus found in the waste “very closely” matched hospital admissions data in New Haven County, said Jordan Peccia, Yale professor of environmental engineering and the project's lead researcher.

As Connecticut reopens its economy and lifts lockdown measures put in place to curb the spread of the virus, researchers said regular testing of solid waste could provide early warnings of new waves of infection and signal the need for more individual testing.

“We were detecting increases in viral genetic material about seven days prior to the increase in the number of confirmed cases (in New Haven County), and three days earlier for hospitalizations,” said Douglas Brackney, an associate scientist with the agricultural experiment station who is involved in the project. “This can be a tool to predict overall community-wide activity and could be used to inform public health policy as well as preparedness in hospital settings and clinics and testing facilities.”

The study took place early during the coronavirus pandemic in Connecticut at a time when testing was not widely available, so with more testing that gap gets smaller, Brackney said.

While COVID-19 testing is expensive and involves a lot of resources, analyzing waste can offer "a snapshot of community- wide activity almost in real time for a large part of state’s population at a much reduced cost,” Brackney said.

But waste analysis is not meant to be a replacement for testing, which Peccia called the “gold standard” given that it provides individual-level data about who is sick. Without that data, health officials cannot do contact tracing to identify who is sick or who they came in close contact with them. 

But data from analyzing waste can provide another piece of information for policymakers and officials to confirm infection rates in their communities.

Testing at the New Haven plant is ongoing, and researchers are providing data to the city of New Haven twice a week. With scaled-up resources, they could provide the data if not every day, then every two days, Peccia said.

Peccia is working to expand the testing to other parts of the state, particularly smaller cities such as New London and more rural areas, where often testing programs are not as robust as they are in more densely populated areas.

He is currently working on securing funding and said he hopes to expand the waste testing to about five or six other cities in the state by Aug. 1.

j.bergman@theday.com