Remember this story about the faecal samples of COVID-19 patients testing positive for two weeks after respiratory samples were shown to be negative? Now there is research showing that sewage can forecast coronavirus cases – a week before those who are infected test positive.
Researchers from Yale University and the Connecticut Agricultural Experiment Station analysed solid waste from the East Shore Water Pollution Abatement Facility between March 19 and May 1 and found the amount of coronavirus matched up with testing totals and hospitalisations.
“It was basically a leading indicator of seven days when it came to testing,” Douglas Brackney, an associate scientist in the experiment station’s Department of Environmental Sciences and a co-author of the study, said.
The amount of virus found in the stool showed a clear link with hospital admissions three days later.
The researchers now hope that sewage testing will be able to be used a surveillance method to detect second waves of the virus before they happen.
The Victorian Government announced this week it would roll out similar wastewater testing across the state from June using a method developed by researchers from the University of Queensland and the CSIRO to spot the “specific nucleic acid fragments” of the virus.
If high amounts are detected, health authorities can begin large-scale testing and quarantine.
“Even if we are not getting cases notified, if we detect it in sewage, we know that there are active cases out there,” Victorian Chief Health Officer, Professor Brett Sutton, said.
“It might tell us about places where we’ve got gaps in surveillance, that people need to come forward for testing or we need to look harder for active cases.”
The method has also been employed in Blackwater, Queensland, where authorities are trying to determine if there are more infections linked to the death of a 30-year-old man there.