KEY POINTS

  • COVID-19 virus levels in Houston wastewater are up by 320% 
  • The data can help predict what the situation will be 'two to four weeks' ahead
  • This signals that the virus is 'rapidly spreading' and will 'likely' continue

The amount of the COVID-19 virus in Houston wastewater has increased by more than 300% since last year. Health officials say the data can help predict what will happen in the coming weeks.

Houston authorities have been monitoring the levels of SARS-CoV-2, the virus that causes COVID-19, in the city's wastewater since 2020. According to current data, the levels of SARS-CoV-2 in Houston's wastewater are now 320% more than the benchmark levels on July 6, 2020.

The chief medical officer for Houston, Dr. David Persse, explained the data can be used to help predict how the virus will spread in the coming weeks, adding that the levels have tripled since the beginning of July, ABC 13 reported.

"The wastewater predicts what's about to happen two to four weeks ahead of time," Persse said Wednesday. "We saw the value of the wastewater dropping, before we saw the positivity rate dropping, before we saw the hospitalizations drop."

In the wastewater analysis provided by the Houston Health Department, one can see the monthly variations in SARS-CoV-2 levels in wastewater since the baseline levels on July 6, 2020. For instance, the virus load on July 27, 2020, was already 39% of the benchmark level, but it dropped to 23% by Aug. 23 and then increased again to 31% by Sept. 28.

In March, the Houston Health Department reported that it detected the virus' U.K. variant in 31 of its 39 wastewater treatment plants. This was a "significant" increase compared to the earlier testing, which found the variant in 21 out of 30 treatment plants. According to the Houston Health Department, this suggested an "uncontrolled" spread of the variant in the community.

The current levels appear to indicate that there will be a further spread of the Delta variant in the coming weeks, the chief medical officer said.

"The virus is spreading rapidly. It's spreading everywhere. It's spreading very intensely. We are at a level of virus in the wastewater that we have never seen before," Persse said. He reportedly described the method of detection as "extremely reliable."

"I can pretty much guarantee you it's only going to get worse over the next four weeks," he added.

An electron microscopic image  that shows SARS-CoV-2, the virus that causes COVID-19
An electron microscopic image that shows SARS-CoV-2, the virus that causes COVID-19 National Institutes of Health / Handout