Read about local bars reopening, antibody tests in our pullout section.

Inclusion lowered ‘positivity’ level that’s been a key for Abbott

Texas included tens of thousands of antibody tests in its daily reports on COVID-19, skewing the recent picture of the outbreak and the state’s response as it scrambled to ramp up surveillance of the outbreak.

About 49,000 antibody tests were included as of Wednesday, or 6.4 percent of all tests reported, according to updated data from the Department of State Health Services. Antibody tests don’t track current infections, only people who have had and recovered from the disease.

Health experts advise against including the antibody tests with standard viral tests for the coronavirus because only the standard tests give a current snapshot of the outbreak. In Texas, the positive antibody tests are not included in the overall case count but have been used in the total number of tests. That created a slightly deflated “positivity rate,” or rate of confirmed cases to total tests.

The health department acknowledged earlier this week that antibody tests made up “a small fraction” of tests reported but only began distinguishing between them and standard viral tests Thursday.

With antibody tests now excluded, the positivity rate has been readjusted up — about half a percentage point for both Tuesday and Wednesday. The positivity rate has been a key measure for Republican Gov. Greg Abbott as he reopens more of the state.

The rate was 5.4 percent as of Wednesday, up a bit from earlier in the week, according to the state data.

Diana Cervantes, who directs the epidemiology program at the University of North Texas Health Science Center, cautioned that the lower positivity rate is likely at least in part because it’s easier for people who aren’t showing symptoms to get tested.

“If you look at the peak on the 13th of April, I’m sure that represented people who had signs and symptoms,” she said, referring to when the rate was at nearly 14 percent. “Whereas you look at it now, the people being tested may have had symptoms, it may be people who have been exposed, it may be mass testing of vulnerable populations — it’s a much broader group. That alone will drive down the percent positivity.”

When asked about the issue during a news briefing Monday, Abbott insisted that the antibody tests were not being included in the official counts. A spokesman

later clarified that he was talking about them being separated going forward.

The governor has since said some counties needed time to separate out the antibody results from their overall counts.

Officials in Taylor County, in West Texas, said in a Facebook post this month that the state health department had instructed them May 6 to remove all antibody cases from their official counts. That day, they removed 82 positive results from antibody tests.

The officials in Taylor County explained that there hadn’t been clear guidance previously from the Centers for Disease Control and Prevention about whether to include the antibody results.

Even with the changes, the state still appears to be nearing Abbott’s goal of completing 30,000 tests per day. In the past six days, the state has averaged nearly 25,000 daily tests.

Abbott stressed again this week that hospitalizations are holding steady across the state and that there is plenty of manpower and medical resources to respond to isolated surges as the state reopens further.

“We’ve never had any challenges with regard to limited hospital capacity, with ventilators, with the ability to treat people who have tested positive for COVID-19,” he said in a TV interview.

Abhi Rahman, a spokesman for the Texas Democratic Party, said in a statement that “Texans don’t feel safe, and manipulating the data isn’t going to help Texans feel comfortable going outside. We must increase our testing capacity and follow the advice of doctors and experts, or we will be hit with a devastating second wave.”