Covid 19 coronavirus: Test wastewater to track virus carriers, says professor

New Zealand should implement a wastewater monitoring system to boost protection against hidden Covid-19 clusters and asymptomatic carriers, a University of Otago academic says.

Professor Neil Gemmell, a geneticist at the University of Otago, is part of a national group, led by the Institute of Environmental Science and Research Limited (ESR).

The group is sampling wastewater, with a view to detecting SARS-CoV-2, the virus that causes Covid-19.

ESR recently received $1.65million in Ministry for Business, Innovation and Employment funding to undertake wastewater-related viral detection research.

Gemmell's research group had already detected coronavirus in wastewater at Dunedin's Tahuna Wastewater Treatment Plant in late March and April, he said.

Big overseas developments in the field showed the required technology was established and effective.

The Washington Post reported late last month the University of Arizona had undertaken periodic screenings of wastewater for coronavirus on its campus, and had detected two asymptomatic students at a dormitory, preventing a sizeable outbreak.

Utah State University Professor of Civil & Environmental Engineering Ryan Dupont collects sewage samples from the dorms at Utah State University. AP Photo / Rick Bowmer

Gemmell was keen to see wastewater monitoring implemented at the country's international airports and ports to detect any "hot spots" of new infection.

This approach could also be deployed regionally to provide monitoring of specific regions, such as Auckland, he said.

"With

"Covid-19 cases re-emerging, albeit currently contained in quarantine facilities, the ability to test sewage at facility, local and regional scales could well be an important part of New Zealand's surveillance safety net."

This approach could also be used to identify "virus circulating in asymptomatic carriers", potentially preventing community outbreaks, he said.