SYDNEY – Australian researchers said on Thursday that they expect to launch extensive testing of raw sewage for the presence of coronavirus within a few weeks to help determine which communities are at risk, after successful regional pilots.
Trials in Queensland by the national science institute CSIRO and the University of Queensland will be used to develop surveillance systems that researchers say will help officials as they begin to reduce restrictions on public movements.
The new project uses an existing system in which crime agencies monitor wastewater, which covers around 57 percent of the population, to detect the presence of illegal drugs in Australian cities.
In experiments in Queensland, scientists were able to detect a gene fragment from a novel coronavirus in untreated waste from two wastewater treatment plants.
Used on a broader scale, waste sampling will be able to detect an estimated number of infected people in a geographical area without testing each individual, CSIRO said. Officials are currently testing thousands of Australians every day using conventional tests.
The director of CSIRO’s soil and water science, Paul Bertsch, said the project would help the government ease national restrictions on the public movement by highlighting problem areas, which allowed many Australians to get out of their homes.
“I see it as an important monitoring tool to reduce restrictions,” Bertsch told Reuters. “When the government subsides, they need to continue to monitor and respond to the outbreak.”
Australia has shut down restaurants, bars and shops deemed “unimportant” while using the threat of fines and even jails to stop public gatherings of more than two people in an effort to slow the transmission of flu-like illness.
Strict measures have helped slow the growth of the daily rate of new infections drastically to a low single rate, from around 25 percent a few weeks ago, totaling around 6,500 infections, including 63 deaths.
Prime Minister Scott Morrison said on Thursday that the restrictions would remain in force for at least another month, even though officials had begun talking about how to start a counterattack.
Health Minister Greg Hunt said a broader detection regime including waste sampling would help indicate whether there were COVID-19 cases in the wider community.
Queensland University Professor Kevin Thomas, one of the researchers at the sewerage test, said the possibility of national testing would be achieved “in a matter of weeks”.
Remote and regional communities, where it is more difficult for health authorities to carry out traditional swab tests, in particular can provide benefits, he said.
Bertsch said wastewater sampling can be carried out every day and while the first tests will be carried out at the wastewater treatment plant, there is the potential to take samples “further pipes” to the periphery level with environmental holes coming down.
Bertsch said Chinese data showed the virus could be detected in feces within three days, faster than many cases detected by conventional tests.