Health & Science

Home testing makes predicting new COVID waves in Texas challenging

New cases of COVID-19 in Texas are increasing again. But predicting how long this wave of infections will continue — and how severe it could be — will not be easy this time around.

Christopher Connelly / KERA News
A rapid COVID-19 test manufactured by Abbott.

The number of reported daily cases of coronavirus in Texas has increased more than fivefold since the beginning of May. But gauging how long the latest surge could last isn't easy.

Dr. Trish M. Perl, a professor in the Department of Internal Medicine at UT Southwestern Medical Center who specializes in infectious diseases said that's due, in part, to more people testing at home.

"None of us are sure about what the crystal ball is looking like," Perl told The Texas Newsroom. "Sometimes we’ve had very good, if you will, insight. Right now, our insight is not as good as it has been because so many people are testing at home. And a lot of the case ascertainment strategies that we’ve had are not necessarily as robust as they were."

The BA.5 variant now accounts for most of the country's new infections. Experts are calling BA.5 the most transmissible COVID variant to date.

On Tuesday July 12, there were about 8,000 new cases reported in Texas, according to statistics from the state's Health and Human Services Department. That follows more than 9,000 new cases reported on July 9.

Dr. Peter Hotez, the dean of the National School of Tropical Medicine at Baylor College of Medicine and co-director of the Center for Vaccine Development at Texas Children's Hospital, said those reports don't show the full picture.

"[Home testing] information is not being sent to the state or to the federal government so there is an undercounting," he told Houston Public Media. "Officially in the United States there is 100,000 new cases a day, in Texas 10,000 new cases a day, in Harris County 2,000 cases a day — but you have to take that with a few grains of salt and it's roughly 10 times higher than that."

Hotez said the positivity rate in Harris County is close to 30 percent, which signals that Texas could see a wave similar to what it saw last year and earlier this year, when the Omicron variant was the dominant strain.

Though true caseloads are more difficult to count, the hospitalization rates for people with COVID are more accurately reported, which helps experts gauge how widespread the latest variants are.

‘As of [Tuesday], we had 672 COVID 19 hospitalized patients in our trauma area" in North Texas, Perl said. "And that that’s an increase of 184 ... since July 1st."

As of Wednesday, there were about 3,300 COVID-19 patients in Texas hospitals, according to the Texas Health and Human Services Department. That total includes 464 in intensive care.

"We are still seeing mostly benign illness, but we are seeing some more severe illness, particularly in the elderly and immunocompromised," Perl said. "So those are two groups that may not respond as well to the vaccines."

She said that one of the reasons for such a fast spread of the BA.5 variant is due to reinfection in people who had a previous COVID strain, even just months ago.

"If you had an infection from an Omicron subvariant two months ago, before the BA.5 was circulating, it appears that you can still get reinfected. So, we are not seeing protection from infection," she said, adding that there is not enough current data to determine how much natural immunity is protecting people from hospitalization.

But Perl said vaccinations and boosters are still protecting most who contract COVID-19 from hospitalization and death.

"It may not protect you from infections, but it is protecting you from the bad stuff," she said.

As BA.5 spreads, experts say now is not the time to let your guard down.

Hotez said Texans should make the most of current opportunities for additional protections — something he said many people are not doing.

"One of the things we've learned from data coming from May ... is that there was a big difference especially in individuals over the age of 50 to whether or not they had two boosts, versus one boost, versus no boost, versus being unvaccinated. And it was a pretty steady gradient," he said.

Perl said more than 70 percent of Dallas County hasn't received a booster, which could factor into how long the new wave of infections will last.

"I would say a lot of this is going to depend on people’s behavior. You know, I understand people are super over this. But the reality is that there are changes in the immunity," she said. "There’s so much we could do to boost immunity right now that would really help us."

She also recommended a return to wearing face coverings indoors, especially for the immunocompromised or other vulnerable populations.

"I want people to be supportive when people wear masks," she said. "They’re usually doing it for a reason. They are vulnerable. They work with someone who is vulnerable. They live with someone who’s vulnerable. And so there’s a reason that they’re wearing a mask. And so, I hope people are supportive of that."

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