Scientists testing wastewater in Brownsville said in January they found more COVID-19 particles there.

The data reflects the COVID-19 report released by Cameron County last month that found 3 thousand new infections. 

The data comes after scientists at UT Health Houston School of Public Health in Brownsville began studying the wastewater last year.

Wastewater samples are collected weekly at one of two Brownsville water treatment plants.

The scientists then use PCR tests to check for the genetic material of COVID-19.

"As the levels of that genetic material in the sewage go up, it means more infection in the community, more people who are shedding that virus into the sewage,” Cameron County Health Authority Dr. James Castillo said.

Castillo says the data is another tool for the county to use.

Scientists only test the water in Brownsville, but Castillo says it reflects what's happening across the Rio Grande Valley.

The state funds the testing program through the Texas Epidemic Public Health Institute.

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