Several states are reporting only positive COVID-19 test results from private labs, a practice that paints a misleading picture of how fast the disease is spreading.
Maryland, Ohio and others are posting the numbers of new positive tests and deaths, for instance, but don't report the negative results, which would help show how many people were tested overall.
"This matters because it gives you a false sense of what is going on in a particular location," said Dr. Eric Topol, director of the Scripps Research Translational Institute. He said states should be required to report both positive and negative results for review by public health experts.
"They should all be pulled together," Topol said. "It should be automatic."
Many states display a more comprehensive picture of their pandemic data, including the total numbers of tests run and those yielding negative results.
The COVID Tracking Project, a private effort to collect testing information nationwide, has found at least nine states that have reported complete results only from state labs, or are missing some reports on negative results.
Melanie Amato, press secretary for the Ohio Department of Health, said her state is collecting only positive test results as many private labs have begun testing residents. As of Tuesday afternoon, the state reported 564 confirmed cases, 145 hospitalizations and eight deaths on its website.
"We don't require private labs to report negative labs in any infectious disease," she said. Asked if that policy might change, she said: "That is a discussion for later down the road."
Similarly, the Maryland Department of Health "is currently reporting the number of positive cases only. We are working on a process to provide timely testing number data," the department told KHN in a statement, adding: "We will provide additional information as soon as it is available." As of Tuesday afternoon, the state was reporting 349 confirmed cases.
In states that do report all test results, the rate of infections varies widely, with some reporting 5% or fewer tests as positive, while others confirm the virus in 10% or more of specimens. The results can change by the day. As of Tuesday, Utah reported 298 confirmed cases out of 5,823 tested, or about 5% positives. Officials noted that some results may have a lag time of up to 72 hours.