In Australia, nine foreign travelers in quarantine in New South Wales have been diagnosed with the Covid-19 virus as authorities have detected more traces of viruses in wastewater, according to the AAP reports.

There are 72 active coronavirus cases across the state as health officials are warning the public to remain vigilant.

“As the weather warms and people start attending more social gatherings, NSW Health is calling on the community to maintain safe behaviors for the COVID-19 virus,” a spokesperson for NSW Health said Sunday.

“Although there have been no locally acquired cases in NSW in recent days, now is not the time to let our guard down.”

Members of the public are reminded to continue to practice good physical distancing and hand hygiene, and to take tests and isolate if they feel unwell.

No locally acquired cases were diagnosed in NSW in the 24 hours until 8 pm on Saturday.

Authorities are urging that people displaying symptoms be tested in parts of western and northwestern Sydney after traces of the Coronavirus were detected in sewage systems.

“The watersheds are consuming wastewater from about 180,000 people,” NSW Health said of a network.

The traces were found in samples taken Thursday from the sewage network serving parts of suburbs including Lipington, Katherine Field, West Hoxton, Hoxton Park, Edmundson Park, Prestons and Miller.

Traces have also been found in a separate sewage system serving 120,000 people in an area covering Quakers Hill, Bella Vista, Kellyville and Baulkham Hills.

“While the detection of the virus in wastewater samples could reflect the presence of older cases of Covid-19 diagnosed in these areas, NSW Health is concerned about the possibility of other active cases,” a statement read.