Health Minister Yvette D'Ath says the new cases is a Gold Coast woman who was already under investigation on Friday, with no other infections detected among 9249 tests in the 24 hours to 6.30am on Saturday.
The woman lives at Mudgeeraba and likely caught the virus from a casual contact at a Bunnings store.
"We understand that being infectious in the community for five days, so from the sixth to the 10th of December, and at this stage, we believe that they are casual contact at a Bunnings store," she said.
"So it just reminds all of us that you can get this virus anywhere and that you have to be vigilant."
The case emerged after six local cases were recorded across the Gold Coast on Friday with exposure sites listed in dozens of venues.
Authorities listed Target at Westfield Garden City in the suburb of Upper Mount Gravatt as the first Brisbane exposure site of the current outbreak on Saturday morning.
Ms D'Ath has also announced sweeping changes to the quarantine rules for Queenslanders identified as close contacts of known cases from January 1.
Fully vaccinated close contacts will need to self-quarantine for seven days, down from the current 14, provided they test negative on day they're notified and on day five.
From day eight to day 14 they will have to wear a mask outside their homes and cannot visit high-risk settings such as hospitals, aged care facilities, schools, childcare centres and prisons.
"We know there is still a risk from day eight to 14 but what we know is that risk is reduced when you are fully vaccinated," Ms D'Ath said.
Unvaccinated household contacts of close contacts will need to follow the same isolation requirements as fully vaccinated close contacts.
Unvaccinated close contacts will need self-isolate for 14 days and get tested on days one, five and 12.
Vaccinated household contacts of close contacts won't have to self-isolate, but get tested on day one and day five.
Casual contacts of known COVID-19 cases won't need to isolate if they test negative on day one, but authorities recommend they wear a face mask.
Meanwhile, businesses listed as exposure venues after visited by active COVID-19 case will no longer have to shut for deep cleaning from January 1 but will still need to close for a normal clean.
"So if it's a restaurant, they've just found out, or cafe, they've just found out they're an exposure site, they may stay closed for lunch so that they can do a clean of the tables and chairs and a good wipe down of the facility and open up for dinner again," Ms D'Ath said.
The health minister defended the restrictions, saying they were be less stringent than the current 14-day isolation requirement for all close contacts.
They're modelled on South Australia's rules, she said, so they align both states which haven't had major virus outbreaks, and at this stage, are the "right mix".