(CNN) — At least four states combined data from two different test results, potentially providing a misleading picture of when and where coronavirus spread as the nation eases restrictions.

Virginia, Texas, Georgia, and Vermont said they’ve been adding two numbers to their totals: viral test results and antibody test results.

Viral tests are taken by nose swab or saliva sample and look for direct evidence someone currently has COVID-19. By contrast, antibody tests use blood samples to look for biological signals that a person has been exposed to the virus in the past.

Combining the two types of tests overstates a state’s testing ability, a crucial metric as nearly all states ease the coronavirus restrictions. Experts have consistently emphasized that for states to reopen, there has to be adequate testing and tracing. Combining the two into one result could also provide an inaccurate picture of where and when the virus spread and mislead officials and the public.

Texas, Virginia and Vermont have said they’ve recognized the data issue and moved to fix it in the past few days. In Georgia, health officials said they’ve been adding both results to their “total tests” numbers since April in line with methodology from the Centers for Disease Control and Prevention.

The CDC has not responded to CNN’s request for comment on whether its guidance includes adding antibody tests to total test numbers. On its website, the database provides daily test results without a breakdown of whether they’re viral or antibody.

“Public health officials need to know how many people in my state or my community currently have COVID-19. They also need to learn how many people had it in the past and potentially are immune to it,” said Elizabeth Cohen, CNN’s senior medical correspondent. “Those are two completely different things.”

U.S. testing data ‘kind of screwed up,’ expert says

In a new report Wednesday, infectious disease experts described US coronavirus testing as disorganized and in need of coordination at the national level.

Testing is currently not accurate enough to be used to make most decisions on who should go back to work or to school, the team at the University of Minnesota said.

“It’s a mess out there,” said Mike Osterholm, head of the university’s Center for Infectious Disease Research and Policy, which issued the report. “Testing is very, very important, but we’re not doing the right testing.”

The number of tests that have been completed — numbers widely reported by states and by the White House — show only part of the picture, the report reads.

“The data is really kind of screwed up,” Osterholm said. “It’s because the public health system is overwhelmed.”

Just this month, researchers described antibody tests in the United States as having “terrible accuracy” with high rates of false positives.

And in recent days, Georgia and Florida have faced questions about the transparency of their coronavirus data reporting.

The-CNN-Wire
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