Missouri’s state health director on Tuesday confirmed that the state has been lumping together different coronavirus test results in a way that can be misleading, despite saying otherwise multiple times last week.
The agency has been combining the results of viral tests, which detect active cases of the virus essentially from the onset of infection, with antibody tests. Antibody tests check for proteins that develop a week or more after infection and show whether a person has been exposed at some point in the past.
Mixing the results makes it difficult to understand how the virus is spreading, and Missouri health Director Randall Williams himself has previously said the two tests should not be conflated. It can give the false impression that the rate of positive test results is declining.
The Centers for Disease Control and Prevention and several other states have admitted to combining the results, but Missouri’s state health department denied doing so when asked by reporters multiple times last week.
“It does not include antibody testing,” Williams said Thursday, before correcting himself this week. “About four states have gotten into a lot of trouble because they tried to conflate their numbers, I think to drive up their numbers, and we don’t do that in Missouri.”
Viral test results should be reported separately, public health experts say. That allows for tracking of how many people have confirmed active infections, the percentage of people testing positive and how those numbers change over time — all crucial for guiding public policy.
Missouri state data were updated to separate the different test types Saturday.
Despite his previous comments stating otherwise, Williams on Tuesday said per the CDC’s previous reporting guidance, Missouri’s health department had been combining results from the two different types of tests. He said he had directed staff not to do so and that senior leadership staff was not aware that results were being mixed.
“Am I frustrated that the directive that I thought was pretty clear did not happen?” Williams said. “Yes, I am,”
He said most antibody tests were performed in Missouri after May 11, implying that data from previous weeks were mostly accurate.
Williams said the state also will start reporting positive test results per patient, so numbers are not inflated by patients who test positive multiple times.
Also on Tuesday, a part of the Ford production plant in the Kansas City suburb of Claycomo was shut down after an employee tested positive for the coronavirus.
Ford spokeswoman Kelli Felker said the transit side of the plant stopped production for about an hour to allow the company to deep clean and disinfect the employee’s work area, equipment, team area and the path the employee had taken at the plant during the day.