Wastewater testing confirmed as best early warning for COVID-19

“This is the first time we’ve looked at retroactive samples,” Dr Ahmed said. “The samples had been taken by our colleagues at UQ as part of the drug monitoring program, and we accessed those.

“We found positive results in samples taken in February, and it was around three weeks later that the first positive cases started to be reported.”

In particular, a sample taken from a Brisbane South wastewater treatment plant in late February 2020 – up to three weeks before the first clinical case was reported – indicated a positive result.

Dr Ahmed said the published research was among the first in the world to show the long lead time between a positive test result and cases showing up in the community.

But he warned that it was not a “holy…