MADISON (WKOW) -- Last week, Madison-area hospitals and clinics opened antibody testing to the public and after thousands of tests, few are coming back positive.
Thetests,which are available at all UW Health, UnityPoint Health-Meriter and SSM Health clinics, determine whether there antibodies designed to fight COVID-19 are present in a patient's bloodstream.
Dr. Jeff Pothof, the UW Health quality officer, said those antibodies can show if your body has been exposed to COVID-19.
"There is a large proportion of people that could have had the disease, they didn't have any symptoms and they could go get a test and it might be positive," he said.
That's why Pothof said hospitals fast-tracked efforts to find a reliable test for this specific strain of coronavirus.
"One of the things that the antibody test is helpful for is kind of this public health understanding of the how the disease has affected our community," he said.
As of Wednesday, UW Health has gotten results for 5303 tests. Pothof said about 1.5 percent have come back positive so far. UnityPoint Health-Meriter reports 433 tests returned with less than .3 percent positive.
"In a way it's good, because it reinforces that the measures that we took to flatten the curve were successful," he said.
Pothof said that could mean the virus didn't spread very quickly through the Madison area. While that means fewer people got sick or spread the virus unknowingly, he said it also means Madison could be far from herd immunity.
Pothof said COVID-19 antibodies don't guarantee immunity, but they can help public health officials predict how the virus could behave if it spikes again.
"With really low prevalence a lot of people are still really susceptible to the disease," he said.
Right now, he said he's hoping for more results before drawing any sweeping conclusions. Relatively few tests have come back and not everyone who may have been exposed has the same access to testing.
"Especially as it pertains to the uninsured," Pothof said. "I think for the insured we've got pretty good guidance, but I think for the uninsured there's a pretty big question mark out there."
The CARES Act requires every insurer pay for the test in full, but for those without insurance, Pothof said UW Health still doesn't know how much will have to come out of pocket. He said that could mean low-income communities won't be represented in antibody data.
"That's exactly the demographic who's most at risk," he said.
As for those who've gone in for the test, some like Tammy Harden are hoping for negative results.
"I know that if we have not been exposed to it, then I know for a fact that I am doing all the proper precautions," she said.
She's taking care of a son with disabilities and a weakened immune system, so she said they went in for the antibody test to confirm they've been doing everything right.
"It's scary," she said. "When I come home from going anywhere I'm doing everything I can to wash my hands, change my clothing because I don't want to pass anything on."
Harden said the trend towards negative results shouldn't discourage anyone from getting tested.
"If you just want to know that you're safe and that you're doing everything correctly to stay safe," she said. "I would recommend anybody to get this test."
All positive antibody tests are reported to the Department of Health Services, but right now they are not a part of the daily report or the public health criteria for pushing back recommendations or restrictions.
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