AUSTIN (KXAN) — Researchers at the University of Texas Cockrell School of Engineering are again testing wastewater samples in Austin for COVID-19 after a lack of funding put the operation on hold in the fall.

UT leadership recently shuffled funding to the program, which will allow researchers to both monitor viral loads in wastewater and sequence test for variants. While researchers haven’t stopped collecting wastewater samples, those samples were not being tested for months.

“At the end of December we started taking daily samples from both of the treatment plants here in Austin, and in about a month or so we’re going to send those off for sequencing,” said professor Mary Jo Kirisits, who is leading the wastewater research efforts at the engineering school. “We’ll have some data on those variants within the next few weeks.”

While more current data is still in the works, samples that were frozen from late last year have now been tested because of that funding. Researchers just got results back on August 2021 samples.

“At that time, delta was highly prevalent both in the clinical cases and what we were seeing in wastewater, and we also had some evidence of the epsilon variant,” Kirisits said.

Other Texas cities using wastewater as key indicator

Meanwhile, the City of Houston has been using wastewater testing to predict COVID-19 hot spots and trends consistently since early 2020.

The wastewater surveillance system in Houston is done by the health department, Houston Water, Baylor College of Medicine and the labs at Rice University. Health leaders in Houston have regularly referred to the data provided by the group to warn the public about alarming COVID-19 trends.

“Ultimately the goal is to help develop an early warning system allowing the health department to identify the city’s COVID-19 hot spots sooner and put measures in place to slow the spread of this disease,” Houston Mayor Sylvester Turner said.

Viral load trends in Houston wastewater
COVID-19 viral load and positivity rate trends in Houston wastewater (courtesy City of Houston)

In September, the group launched a COVID-19 wastewater dashboard that allows people to follow trends for the Houston area as a whole, all the way down to their zip code. The dashboard is updated weekly.

That dashboard shows, compared to the beginning of the pandemic, there has been a more than 1,600% increase in viral load detected in wastewater across Houston. It’s showing a testing positivity rate of just under 30%. The dashboard was updated at the end of December.

Houston’s health department also tests wastewater at local schools, not just for COVID-19 but for flu, too. That data is provided weekly on the dashboard as well.

Why isn’t Austin doing the same?

As for why Houston is able to put forward significant amounts of data from its wastewater testing that Austin is not, Kirisits said, “it’s just a question of funding.” Still, the data collected will inform health leaders on how prominent certain variants really are in Austin and how much COVID-19 is in our community overall.

Research still needs to be done to determine how much viral load in wastewater equates to a single COVID-19 positive case. That’s something data collected from local research groups, like the one at UT, will help determine.

“There’s actually requests for proposals right now from the CDC, because they want that data in terms of what is the shedding for these variants,” Kirisits said.