Wisconsin Will Start Antibody, Wastewater Testing to Track COVID-19
The Wisconsin National Guard has been providing free diagnostic COVID-19 testing across the state. Now the state will be conducting antibody and wastewater testing to broaden its understanding of the virus. (Photo © Andy Manis)

Tests are latest moves by the state to contain virus until vaccine discovered. 

Through a partnership between several state agencies, laboratories and universities in Wisconsin, two new public health studies will get underway later this month to better understand where the coronavirus has been and which communities are at risk for future outbreaks.

Antibody testing tells health officials where the virus has been, and testing water at wastewater treatment plants tells health officials where the next surge is likely to hit.

“One of the most challenging things about COVID-19 is that as a new virus, there is still so much to learn,” said state Department of Health Services Secretary-designee Andrea Palm in a statement. “That is why this type of research is essential to our statewide efforts and until there is a vaccine, we must do everything we can to protect our communities and ensure that we are safely reopening the state.”

Antibody testing will begin later this month in the 10 Wisconsin counties of Dane, Milwaukee, Brown, Eau Claire, La Crosse, Ozaukee, Polk, Racine, Waushara and Wood, according to the state Department of Health Services. 

These counties were chosen because they have resident volunteers already participating in studies through the University of Wisconsin-Madison’s Survey of Health Wisconsin. By partnering with this division of the university, the state health department can more quickly get the antibody testing up and running, as there is already a pool of volunteers in place, said Dr. Ryan Westergaard, the state’s chief medical officer on a call with reporters Wednesday.

Westergaard said antibodies indicate if a person has been infected with COVID-19 in the past, even if they did not experience symptoms. Antibody testing, as opposed to the diagnostic test that determines if a person is positive for COVID-19,  helps in understanding how many people were infected with COVID-19.

Study participants will receive antibody testing quarterly over the course of the next year.

Funding for the antibody testing comes from the Centers for Disease Control and Prevention. 

While antibody testing provides a more comprehensive look at the true number of people who have had the virus in the past, the second test being rolled out by the state tests the likelihood of a potential outbreak in the future. 

The Wisconsin State Laboratory of Hygiene, the UW-Milwaukee and the state Department of Natural Resources will collaborate for the second study, Wastewater Surveillance of SARS-CoV-2 in Wisconsin.” 

This study will test samples from wastewater treatment facilities in both populated areas and rural portions of the state in order to determine the current concentration levels of virus genetic material found in the sewage. 

If the virus is detected or virus quantities are increasing, public health officials can proactively adopt measures to minimize transmission of the virus and prepare for a surge. Conversely, wastewater samples may be able to detect areas with low levels of infection. 

Surveillance of wastewater will provide public health officials with the opportunity to identify the magnitude of COVID-19 transmission, circulation within a community, and potentially, early warning detection of outbreaks. 

Results for this study should begin coming in later this summer, as the state lab begins routine sampling of wastewater. The study will run through next June.

“Routinely monitoring COVID-19 in wastewater is an effective method to assess community-wide presence and levels of the virus,” said Dr. Jonathan Meiman, Chief Medical Officer for the DHS Bureau of Environmental and Occupational Health and Occupational Disease Epidemiologist. “This approach is not designed to replace the existing public health surveillance but will help supplement the current practices and mitigation efforts.”

As of Thursday, 23,454 people, an increase of 256, have tested positive for the virus. There are 3,128 people hospitalized, an addition of 32 patients from Tuesday and 712 people have now died from the virus in Wisconsin.