Health authorities in Brisbane are scrambling to locate close contacts of a COVID-19 case who hosted a party at his home and visited several venues while he was infectious.
The man, aged in his 20s, partied with friends and visited numerous public locations while awaiting his swab result - despite being instructed to isolate until he had returned a negative test.
The man, from Strathpine - a suburb in the Moreton Bay Region on the outskirts of Brisbane, roughly 22 kilometres north of the CBD - tested positive for the virus on Friday night, Queensland Health confirmed.
He is infected with the B.1.1.7 strain, also referred to as the UK variant, a mutation known to be more transmissible and more deadly than older variants.
About 25 people who attended the party at the man's home have been located, Queensland Health said on Saturday. All the guests have been ordered into quarantine and will undergo testing.
The man also visited at least 15 venues across Strathpine, Lawnton, Eatons Hill and East Brisbane while he was infectious.
Health officials say the man was infected by a 26-year-old male friend from Stafford, a northern suburb of Brisbane, who tested positive for the virus on Thursday.
Authorities have now identified 24 potential exposure events across Brisbane, nine of which were visited by the Stafford case.
More sites could be added if guests who attended the Strathpine man's party test positive for the virus, Queensland Health said on Saturday.
"More locations may be added after it was revealed the Strathpine man hosted a gathering of around 25 people at his home between being instructed to isolate and getting his positive test results," the department said.
Eighteen contacts of the Stafford case are currently self-isolating and undergoing testing.
Speaking to reporters on Saturday, Queensland Premier Annastacia Palaszczuk said she is "comfortable" with the situation - as long as Brisbane residents continue to maintain social distancing and get tested when presenting symptoms.
"We are not seeing large-scale community transmission, this is a close contact," she said.
The nine sites visited by the Stafford man include the Westfield Shopping Centre in Carindale, Bunnings in Stafford and Gasworks at Newstead.
Contact tracers are paying particular attention to the Carindale mall and Mama's Italian Restaurant in Redcliffe. Officials say it's likely the 26-year-old had numerous interactions at the venues as he spent considerable time at both, increasing the likelihood of transmission.
People who visited the restaurant during the same period as the case last Sunday have been ordered to quarantine immediately for 14 days.
The Eatons Hill Hotel has also been identified as a location of concern linked to the Strathpine case.
Chief health officer Jeannette Young said both cases are genomically linked to a Princess Alexandra Hospital doctor who was diagnosed on March 12.
The doctor visited four venues in the city's south while she was infectious.
Dr Young said it's likely the Stafford man caught the virus from an intermediary yet to be identified, although it's possible there could be two missing links between the doctor and the 26-year-old.
The cluster has sparked a lockdown of Brisbane City and Moreton Bay council area hospitals, aged-care facilities, prisons and disability services providers.
Western Australia on Saturday night announced new restrictions requiring all visitors from Queensland to self-isolate for 14 days.
New South Wales, Victoria and the ACT have declared the two Queensland council areas as hotspots. All travellers arriving from Brisbane City or Moreton Bay must self-isolate and get tested upon arrival, while Tasmania is warning travellers to get tested if they become ill.
There are currently 71 active cases of COVID-19 in Queensland, including imported cases detected at the border.