Health experts ‘cautiously optimistic’ by Texas’ COVID declines. School may change that
The lower case counts and a decline in hospitalizations of patients with the novel coronavirus across Texas and the Dallas-Fort Worth area is encouraging, but public health experts and epidemiologists warn it is not enough.
With schools reopening their doors and the upcoming Labor Day weekend, public health experts worry that an increase in the virus’ spread could be on the horizon.
“I am cautiously optimistic,” said Catherine Troisi, an infectious disease epidemiologist at UTHealth School of Public Health in Houston. “Because as we’ve seen, things can change very quickly.”
In Tarrant County, hospitalizations of COVID-19 patients have dropped to their lowest levels since June, as have emergency room visits for COVID-19-like illnesses. And the virus’ spread locally has begun to decline, said Rajesh Nandy, an associate professor of biostatistics and epidemiology in the University of North Texas Health Science Center’s School of Public Health.
The R0, pronounced “R-naught,” is a calculation used to estimate the number of new infections transmitted by a single case. If it’s above one, it means that each case is spreading to more than one person. If it’s below one, it indicates the virus’ spread is on the decline.
In Tarrant County, Nandy, who has been closely tracking Tarrant County’s data, said the R0 is now at about 0.95 — a decline from a high of 1.35 in late June and when it hovered above 1 in July.
But experts stress that caution is still needed.
COVID-19 Hospitalizations over Time
Coronavirus daily hospitalization counts in Texas and the larger Trauma Service Areas, beginning April 8, 2020. Data provided by Texas Health and Human Services.
“The numbers have stabilized, but at a very high rate,” said Benjamin Neuman, the head of Texas A&M University-Texarkana’s biology department and a virologist who has worked with coronaviruses for over two decades.
On Wednesday, Texas’ 4,923 new cases made up a little over 10% of the at least 49,787 reported for the U.S. that day. The state accounts for 8.8% of the nation’s population.
For the week ending Aug. 19, Texas averaged 6,369 new cases a day, based on state data. While a roughly 30% decline from the seven-day average of 9,314 cases reported for the week ending July 19, it’s still about six times higher than the seven-day average of around 1,000 new cases being reported back in May.
“We’re still at a really high level of cases,” Troisi said. “We are not out of the woods yet.”
For the country to consider fully reopening, Neuman recommended that new daily cases should be less than 100 across the U.S.
“You can tell that the country is nowhere near that number,” Neuman said. “Even if every other state was case-free, Texas alone would be holding back the United States — preventing us from reopening.”
Students returning to the classroom will only be introducing more chances for the virus to spread, experts said, increasing the risk of a possible surge. And by the time it’s clear a surge is happening, we’ll already be at a disadvantage, Nandy said.
“By the time we realize that things are taking a turn in the wrong direction, it’s already too late because of the lag,” Nandy said. “When we clearly see that there is another surge, that means the surge is huge because there is a lot of new cases which are not yet detected.”
The state announced Thursday that Texas’ public schools will be required to report COVID-19 cases to the Texas Department of State Health Services, which will post the totals publicly. To mitigate the virus’ spread, schools have gathered personal protective equipment and encouraged self-screening of symptoms. But to identify cases, ultimately increased testing and contact tracing will be needed, Neuman said.
Troisi recommended schools test a random sample of people every few days in order to get a sense of whether the virus is spreading on campus and in the community.
While demand for testing is still high through Tarrant County’s public health sites, across the state it has fallen, officials said. A backlog of tests has also injected older cases into the state’s most recent totals, affecting the postivity rate — a key metric Gov. Greg Abbott has said he is monitoring.
In Tarrant County, the public health department has reported hundreds of cases as a result of the backlog, with some over a month old. Tarrant County Public Director Vinny Taneja expressed concern that because of the backlog, contact tracing cannot be done for those cases — leaving the county with an incomplete picture of the virus’ spread.
On Aug. 12, an addition of over 124,000 new tests dramatically pushed the state’s seven-day average positivity rate — the number of positive cases out of those tested — down from a record high of 24.5% to 16.08% in just one day. After dipping to around 11%, Texas’ positivity rate was at 14.38% as of Thursday.
Despite the decline, experts say the rate is still too high and that it should remain below 5% for efforts like contact tracing to be effective. Abbott has said that for him to consider reopening bars or scaling back restrictions, the positvity rate would have to consistently remain below 10% for at least two weeks, among other factors.
On Aug. 13, Abbott said DSHS was investigating the rise in the positivity rate, and a spokeswoman for DSHS had pointed to coding errors and an upgrade to the state’s lab reporting system that allowed DSHS to clear test results that had previously been reported to the patient, but not entered into the system.
Abbott told KXAS Channel 5 on Wednesday night he is more confident in the numbers after after the reasons behind the faulty data were identified.
“One leading reason is that at least three of the primary labs that were providing information about test results had backlogs — some of which were in the tens, maybe hundreds of thousands — and hence, there were many tests that these labs had not reported,” Abbott said.
A DSHS spokeswoman told the Houston Chronicle that the backlog consisted of about 500,000 viral tests, with some dating as far back as March.
The data discrepancies have caused some local officials to question its reliability, with Collin County putting a disclaimer on its COVID-19 dashboard that it has “no confidence” in the data being provided.
But Troisi said right now, even with its coding delays and errors, it’s the best Texas has available.
“You take it with a grain of salt,” Troisi said. “It’s all we have to look at right now.”
And from what it does show, Troisi said Texans can’t let up on best practices.
“We just can’t let our guard down. We need to keep wearing our masks, only going out when we need to and when we do... being at least six feet away from other people,” Troisi said.
This story was originally published August 21, 2020 at 3:37 PM.
