Queensland has recorded three new local cases of coronavirus on the state's first day of its snap lockdown.
The three new cases were close contacts of existing infections and include the younger brother of a 19-year-old casual receptionist at Prince Charles Hospital.
A close contact of the Portuguese restaurant cluster and a close contact of a Virgin flight crew member were also among the new cases announced today.
LIVE UPDATES: Brisbane hospital worker's brother 'tests positive'
https://twitter.com/AnnastaciaMP/status/1410026212156534784Queensland Premier Annastacia Palaszczuk described the cases as "good news" as the infections were in quarantine.
"We are considering these low risk," she said.
"So this is very good news."
Chief Health Officer Dr Jeannette Young said the brother of the unvaccinated hospital worker had visited Magnetic Island and became infectious on June 26.
He attended a school holiday tennis camp at Shaw Park Tennis Centre at Wooloowin on June 28, areas of concern contract tracers will be targeting to prevent the rampant spread of the virus.
EXPLAINER: Everything you need to know about the Queensland lockdown
The Virgin crew member worked on five flights whilst infectious, with public health teams racing to determine whether they were infectious before going into quarantine.
"They were in quarantine and we're just working through whether they were out and about before they went into quarantine during their infectious period," Dr Young said.
The close contact linked to the Portuguese restaurant cluster was in hotel quarantine during their entire infectious period.
The state's active number of COVID-19 cases has climbed to 42, which Dr Young labelled "concerning".
"A lot of these active cases are the Delta variant and we know that is very contagious," she said.
More than 18,000 people came forward for testing yesterday, Dr Young praising the effort as a "magnificent response".
READ MORE: Multiple flights among Queensland's exposure sites
In positive news, the Brisbane family who went to Magnetic Island in Townsville travelled via car and were not "out and about" at the ferry terminal of previous concern.
The 19-year-old hospital worker had travelled with her family between her home in Sandgate to Magnetic Island at the end of last week.
"I was concerned about that ferry terminal because of the linkages between Palm Island and Magnetic Island," Dr Young said.
"That significantly reduces the risk for the people from Palm Island."
People from Palm Island frequently visit Townsville, which meant restrictions could not yet lift for the northern city.
READ MORE: Palaszczuk questions AstraZeneca rule change, Pfizer supplies run low
"It's really important that all those people in Townsville City, Magnetic Island, and Palm Island remain in their homes or residences for that three-day period, except for the four reasons you can leave,'" Dr Young said.
Queenslanders have so far been mostly complying with lockdown measures, Deputy Commissioner Steve Gollschewski said.
"The overall levels of compliance is good," he said.
"We intercepted 1759 vehicles and only had to turn around three so that's very encouraging."
There were 28 people found without masks, who later agreed to wear one after being stopped by police. However, one person was fined for refusing to wear a mask.
"One person yesterday in Nambour, a 36-year-old male, refused on several occasions to wear a mask and was issued with a $200 penalty," Commissioner Gollschewski said.
"So the message to the community is of course we'll work with you, please comply with these restrictions."
Queensland's lockdown, spanning 11 Local Government Areas, is due to end at 6pm on Friday.
The wide-ranging lockdown includes South East Queensland, Townsville city, Palm Island and Magnetic Island, given the 19-year-old woman flew around the state during 10 days while she was infectious.
The reason why the hospital worker may not have received the vaccine is that there "seemed to be a view" she did not fall into category 1A.
A "full investigation" as to why the hospital worker did not get the jab will be established.
