Queensland has recorded 18 new cases of COVID-19 and all of those people were infectious while moving around communities from the Gold Coast to Townsville.
One person had visited an aged care centre in the Brisbane suburb of Holland Park and Health Minister Yvette D'Ath said residents and staff were being tested.
The increase in daily cases has not come as a surprise as health authorities concentrate on the number of people needing hospital or intensive care.
The newly diagnosed people are vaccinated and not showing signs of being seriously unwell, Ms D'Ath said.
"We can expect more cases, that's exactly what we're reporting today, we expect these numbers will keep growing," she said on Thursday.
Ms D'Ath pleaded with Queenslanders to resume wearing masks in indoor venues and warned there was an "active discussion" about certain settings.
"Please get out those masks, start wearing them anywhere in Queensland," she said.
The warning comes as three previously announced cases were confirmed to have the Omicron variant, including a man who flew from Newcastle to Townsville via Brisbane.
Another four Omicron cases were confirmed in Queensland on Thursday, including two in home quarantine and two cases acquired overseas, Ms D'Ath said.
