From Texas Observer: Is Texas Inflating Its COVID-19 Testing Results With Antibody Test Numbers?

According to Texas Governor Greg Abbot’s communication John Wittman, Texas has doubled its rate of testing for the coronavirus:

Gov. Greg Abbott’s communications director John Wittman told ABC News that the amount of testing has doubled since reopening, contributing to the rise in cases.

“Since [COVID-19 testing] started, we did 330,000 tests in March and April. Since May 1, we have done over 330,000 — so in 16 days we have doubled our testing from the previous entire two months,” Wittman said.

“The governor has been clear that as the state of Texas conducts more tests, we will see the raw number of cases rise,” Wittman said. “However, the [rolling seven-day] average positivity rate has steadily declined from our high April 13 [of a bit more than 13%] to around 5% today. Our hospitalizations remain steady, and Texas has one of the lowest death rates per capita in the nation.”

Texas began reopening after its stay-at-home order was lifted on April 30.

Sounds great.  Who can argue with more tests being done?  Except, the Texas Observer has an article up that indicates the state is mixing two different types of tests into their announced totals.  

Texas health officials are combining some antibody tests along with more common viral tests in statewide COVID-19 tracking data. Experts say this muddies the data and potentially helps pad testing numbers while giving the public a distorted view of the current spread of the virus.

As of Friday, Texas reported administering nearly 646,000 COVID-19 tests since March, and almost 45,200 cases of the virus. The data, published by the Texas Department of State Health Services (DSHS), appears to show the number of viral tests—that is, a swab of a person’s nose or throat to detect an active infection—and the number of positive cases connected to those tests. But mingled with the viral test numbers are antibody tests—which use a blood sample to determine if a person has developed antibodies to fight coronavirus—and their results. These tests are generally used to determine whether someone may have had the virus in the past, not necessarily whether they are currently infected.

It’s unclear what portion of the state’s case counts so far are based on antibody tests, but the co-mingling of the two types of tests raises questions about the validity of the state’s data, which has influenced efforts, largely by Republican government officials, to quickly reopen the state’s economy.

As pointed out in the article, the swab based test determines if you have the RNA from the coronavirus present, which means you have an active infection.  Antibody testing, on the other hand, determines if you developed antibodies to a past infection of the coronavirus.  Therefore, the swab test is for the present, while the antibody test is for the past, to put it in the vernacular.  

The reporter tried to get an answer out of the state department of health on why the antibody test is being reported with the swab tests:

A spokesperson for DSHS confirmed to the Observer that the agency includes “some antibody results” in its official statistics. “Now that antibody tests have become more available, we are working to provide data by type of test and whether cases are confirmed cases of active infection identified by [viral] test or probable cases identified by antibody tests,” Lara Antone, the spokesperson, wrote in an email Thursday evening. She did not answer specific questions about how many of the tests or positive cases included in Texas’ count so far are based on antibody tests, why they are being included, or when these test results will be delineated.

There’s no accurate way to meld the two kinds of tests. Adding just the antibody test numbers and not the results inflates the state’s testing numbers and artificially lowers the infection rate, while grouping “presumed positive” cases from antibody tests with active positive cases from viral test totals conflates the two.

This opacity is part of a broader patchwork of county and state data that fails to accurately track COVID-19. DSHS data excludes some positive cases in prisons, significantly undercounting total infections in at least two East Texas counties, the Observer reported last week. State officials have also declined to release information about infections in other major outbreak centers, like nursing homes and meat processing plants, and have not released detailed racial and ethnic breakdowns of cases and deaths around the state.

The number of daily tests and the rate of positive cases are among the main metrics public health experts point to as critical in determining whether it is safe to start reopening public spaces. Texas has lagged far behind, ranking near the bottom of all states in tests per capita, and trailing Governor Greg Abbott’s goal of 30,000 tests per day. Yet the governor accelerated the state’s reopening this month, despite still-limited testing and warnings from health experts and local officials that true case counts around the state were likely higher than reported.

I had not heard that Texas was trying to pull the same shit as some other states like not including the testing from prisons, meat processing plants, or nursing homes.  But this smells like Abbot is fudging the numbers to make the percentage of positive coronavirus cases appear much lower.  

I’d like to hear from any Texans who have read or know of something similar to this article.

Tagged with:
Notify of

This site uses Akismet to reduce spam. Learn how your comment data is processed.

Inline Feedbacks
View all comments