The number of COVID-19 cases connected to the Crossroads Hotel outbreak in Casula in Sydney's southwest has jumped by three to 37.
Three new COVID-19 cases in NSW are linked to a southwest Sydney pub cluster, taking the total number of connected cases to 37.
NSW Health reported 10 new COVID-19 cases in the 24 hours to 8pm on Wednesday from almost 23,000 tests, with six cases locally acquired.
Three-of-the-six cases - a child of a known case, a man in his 30s who was a contact of a known case and a male patron in his 80s - are connected to the Crossroads Hotel in Casula, which an infected Melbourne man attended on 3 July.
At least 21 of the 37 known cases in the cluster were hotel patrons.
NSW Chief Health Officer Kerry Chant said two other cases had arisen since 8pm on Wednesday, including a teen who attended the Hurricane Grill in Brighton-Le-Sands on 11 July with a known case. The site has been closed for cleaning.
Another case involved a NSW man who returned to Ballina from Melbourne on Jetstar flight JQ466, with all passengers on that flight being contact traced.
"Obviously we are concerned when we find cases that can't be linked back because it does indicate we have missed a chain," Dr Chant told reporters on Thursday.
Dr Chant this week warned COVID-19 clusters would pop up because of the "stealthy" nature of the virus and the rapidity with which the virus could spread.
NSW Health on Wednesday confirmed the "patient zero" of the outbreak was most likely a Melbourne freight company employee who attended the Crossroads Hotel on 3 July for a work party. Six of his colleagues have since caught COVID-19.
The man entered NSW on 20 June, before the state's border with Victoria closed.
NSW Health Minister Brad Hazzard warned it was unrealistic to expect the state to frequently record zero COVID-19 cases as the virus could bubble away under the surface.
Mr Hazzard told 2GB radio on Thursday that young Australians in particular needed to keep in mind the consequences of their actions amid the pandemic.
"If they happen to have the virus they can be super-spreaders with great skill and acumen," he said.
"We've got a young bloke from that latest cluster ... he had one of the highest infection levels that we've ever seen."
NSW Health on Wednesday also named several venues where confirmed COVID-19 cases spent time, including the YMCA at Revesby, Wests Leagues Club at Leumeah, Macarthur Tavern in Campbelltown and Casula Kmart.
The Milky Lane burger joint in Parramatta and the Bavarian Macarthur restaurant in Campbelltown were later added to the list as well as Woolworths in Bowral.
Victoria on Thursday recorded a record 317 new COVID-19 cases.
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