The Department of Health and Human Services has listed three high-risk locations in Melbourne following the discovery of three new COVID-19 cases in the metropolitan community.
People are urged to get tested for coronavirus if they visited Mentone or Parkdale Beach between 10am and 4.30pm on December 27, Century City Walk and Mocha Jo's in Glen Waverley between 1.30pm and 5pm on December 28 and Katialo restaurant in Eaton Mall, Oakleigh, between 7pm and 8.15pm on December 28.
The three positive cases were the result of community transmission in Mitcham, Hallam and Mentone. The patients who have tested positive are two women in their 40s and a woman in her 70s.
Victoria's COVID-19 response commander Jeroen Weimar said the active cases were concerning.
He said everything was being done to ensure all relevant exposure sites and close contacts were identified.
"We have three cases that are self-isolating at home and are being supported and monitored by the Department of Health and Human Services," Mr Weimar said.
"We have been in this position before and we are deploying our full outbreak approach around these cases. Extensive contact tracing is underway and as a result there are currently more than 40 primary close contacts that are being supported to isolate immediately."
Contact tracing will continue overnight in an effort to determine how these cases presented with more close contacts are expected to emerge.
"At this point, our priority is on making sure we've got the right supports in place for the close contacts (primary and secondary) and that people are getting themselves tested," Mr Weimar said.
"We are so thankful that these people did the right thing and got tested. We always knew this virus had us in a precarious position and we need to make sure we do everything we can to stamp out any further transmissions.
"Now more than ever people should not let down their guard."
The list of exposure sites can be found at www.dhhs.vic.gov.au/case-locations-and-outbreaks People can also phone the COVID-19 hotline on 1800 675 398 for more information.
THREE reported new COVID-19 cases in Melbourne could spell trouble for Victoria's 61-day streak without community transmission.
It's understood the three cases are from three different suburbs - Mentone, Mitcham and Hallam - and are not linked to returned travellers.
Authorities are investigating where the cases have come from and if they are linked to NSW cases.
It is believed the three had not recently travelled to NSW, where 18 new cases of community transmission were recorded on Wednesday including two linked to the Wollongong area and six from a new cluster in the inner-west of Sydney.
NSW Health has urged anyone who spent time in the Illawarra-Shoalhaven region in the past fortnight to be on the lookout for symptoms and get tested should any develop.
The three Melbourne cases and close contacts are now in isolation.
Interviews with the cases and close contacts were occurring late on Wednesday.
On October 26, Victoria reported its first day since June 9 of no new community-transmitted cases of COVID-19.
The state has had a clear streak since October 29 and marked up 61 days on Wednesday morning.
The news of three news cases comes as Victoria tightens its borders with NSW.
People who have visited the Blue Mountains or Wollongong regions from December 27 will be barred from entering Victoria from midnight on Thursday.
People intending to return to Victoria from these areas between midnight on Wednesday and 11.59pm on Thursday must apply for a new travel permit through Service Victoria, must get tested within 24 hours of returning to Victoria, and must self-quarantine at home for 14 days from when they last left the region.
Nobody who has visited these areas will be able to enter Victoria after December 31.
The state government urged anyone already in Victoria who had been in Wollongong or the Blue Mountains since December 27 to get tested and stay at home until a negative test result is received.
No one who has been in the Northern Beaches area, Greater Sydney, and the NSW Central Coast in the past 14 days is allowed to come into Victoria. The states' border remains closed.
The Victorian government warned anyone arriving at the road border from affected areas would be turned away and would have to find alternative accommodation in NSW.
The government said border restrictions were being reviewed daily. It strongly advised Victorians not to travel to NSW due to the risk of needing to undertake hotel quarantine for 14 days upon return.
Read more: COVID-19 risk across greater Sydney spikes
Anyone found to have entered Victoria without a valid permit of exemption may be subject to penalties of more than $1652. If someone intentionally provides false information on their permit application, they face fines of $1652 or a penalty of up to $9913.
The rest of regional NSW is designated as a "green zone".
Residents in border communities still do not require a permit, however must travel with their driver's licence or other valid photo ID with their address details.
Testing site details, including opening hours, are available at dhhs.vic.gov.au/where-get-tested-covid-19.
The government said people could access information regarding COVID-19 via the Department of Health and Human Services website or by calling 1800 675 398.
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