There have been three cases of COVID-19 detected in the Glenelg Shire overnight.
Portland District Health says all three cases are from the same household.
It comes after repeated detections of viral fragments in the region's wastewater were reported this week.
COVID-19 was unexpectedly detected on October 4, 6 and 7.
"We have been notified that within our local community there are three three confirmed cases of COVID-19 from the one cluster all from the same household," PDH said in a statement.
"At this stage we don't know precise details, but the Department of Health and the Barwon South West Public Health Unit will be providing specific information about any exposure sites and we will share that with you as soon as possible.
"In the meantime, we encourage anyone with COVID symptoms such as fever, dry cough and tiredness to isolate and get tested as soon as possible."
A drive through testing clinic is running at PDH until 4pm today by booking in advance: Bit.ly/PDHCovidTest.
The hours and location will be constantly reviewed and the latest information on this and any other information will be available on the PDH Facebook and Instagram pages.
The most recent information on vaccination appointment availability will also be available on the PDH social media. Please follow these to keep up to date.
Colac recorded one new COVID-19 case yesterday, bringing the cluster to 32 active cases across the Colac-Otway Shire.
There are no new exposure sites and Colac Area Health said the cases are contained and have been isolating.
Zero new cases in Warrnambool for sixth consecutive day
Meanwhile Warrnambool has recorded its sixth day in a row without new COVID-19 cases.
A further three people have recovered from COVID-19 in Warrnambool.
The city's cluster is now sitting at 19, with 15 active cases in Warrnambool across five households, four active cases in Moyne Shire across three households and one active case in Corangamite in one household.
There are no new exposure sites.
South West Healthcare chief executive Craig Fraser welcomed the news after a COVID-positive couple from Geelong visited the region last weekend, resulting in multiple exposure sites around the city.
Today's testing site is the clinic at Merri Street open until 4pm via appointment only.
The South Warrnambool Testing Clinic and Deakin University Testing Site are closed today.
The Leura Oval at Camperdown is open Tuesday, Wednesday and Friday from 3.30pm to 4.30pm.
Turnaround times for the majority of tests is between 24 and 48 hours, South West Healthcare said.
"We appreciate people isolating whilst they are awaiting tests," the service said in a statement.
"To stop the spread of COVID-19 don't visit anyone in their homes or let anyone into your home if they don't live there, limit how much you move around the community, social distance and keep up your hand hygiene.
"Thank you all for your support and for doing the right thing to keep our community safe."
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