Routine testing at the Castlemaine wastewater treatment facility has detected fragments of COVID-19.
Castlemaine's CHIRP Community Health has advised residents and visitors to Castlemaine, Campbells Creek, Chewton, Harcourt, Newstead and Maldon to get tested for coronavirus if they have any symptoms.
A drive through testing clinic will open from 10am to noon on Saturday, December 19 and Sunday, December 20 at CHIRP Community Health, 13 Mostyn Street, Castlemaine, while the Bendigo Health COVID-19 screening clinic at Stewart Street, Bendigo is open from 10am to 5.30pm daily.
Coronavirus symptoms to watch out for are a loss or change in sense of smell or taste, fever, chills or sweats, cough, sore throat, shortness of breath and a runny nose.
The community health service said the Department of Health and Human Services confirmed low levels of viral fragments were detected in a waste water sample on December 15.
It said the result is unexpected, given there are no recently confirmed cases or diagnosis of COVID-19 in the area and no known cases of community transmission in Victoria at this time, as Victoria marked its 49th day without any cases of community transmission.
Samples of untreated wastewater are routinely analysed for fragments of coronavirus at more than 60 locations in Victoria, including in Castlemaine and Bendigo.
Mount Alexander Shire council's emergency manager coordinator Luke Ryan urged community members to remain calm but vigilant.
"While the risks associated with the detection of viral fragments in wastewater is low, this is a good reminder that COVID-19 is part of our lives and we must all remain vigilant," Mr Ryan said.
"Practice good hygiene, maintain physical distancing and continue to wear a mask in places like supermarkets, on public transport and in situations where you can't stay at least 1.5 metres away from others."
The discovery of COVID-19 in Castlemaine's sewerage system comes as a virus cluster associated with Sydney's Northern Beaches has grown to 28 cases, prompting the state government to introduce a permit system at the Victoria-NSW border.
The government also warned against travel between the two states, with residents of Sydney's "red zone" not allowed entry into Victoria.
Department of Health and Human Services testing and community engagement commander Jeroen Weimar said the Victorian government would now meet all incoming flights from NSW, to make sure all arriving passengers understood requirements.
Mr Weimar said the government would contact trace all passengers who had arrived from Sydney since December 11, advising any who had been exposed to high risk sites to get tested and self-isolate.
A total of eight cases of COVID-19 have been reported in the state's rebooted hotel quarantine.
Victorian health authorities received a total 7570 test results in the day to Friday.
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