The QLD move comes after a cleaner at a quarantine hotel in Brisbane tested positive yesterday to the mutant strain and was in the community for five days.

All residents in those areas need to stay at home unless it is for essential work, providing healthcare for a vulnerable person, or essential shopping and exercise in your neighbourhood.

Long queues had already formed at supermarkets within an hour of the announcement.

If you do go outside, masks in those areas will be mandatory, however children under the age of 12 are exempt.

Premier Annastacia Palaszczuk said it was a harsh but necessary decision.

"Think of it as a long weekend at home, we need to do this," she said.

"If we do not do this now it could end up being a 30-day lock down.

"If you're scheduled to go and visit some friends in another part of the state, I would urge you to reconsider that and to stay at home."

People living in the lockdown areas will be allowed two visitors per day at their homes but they have to come "for specific purposes, such as supporting someone".

Queensland recorded nine new cases of coronavirus overnight, after about 13,000 tests, however all were in hotel quarantine.

Chief Health Officer Dr Jeannette Young recommended the swift action.

"It'll be too late if on Monday I stand up here in front of you and say we've had 10 cases and they've been out infectious in the community infecting people," she said.

"We can't put it back in the box.

"We've got to act before we get the cases."

Score of close contacts

Ms Palaszczuk said they had examined 689 "movements" of the cleaner while she unknowingly moved in the community for five days, around Sunnybank Hills, Algester, Calamvale and Brisbane's CBD.

Authorities had also identified 79 close contacts of the woman, so far those who were symptomatic have been tested.

Results are yet to be returned.

The quarantine hotel where the woman worked has also been placed into lockdown.

Others at risk of infection to self-isolate

Chief Health Officer Jeannette Young has asked anybody who has been in Greater Brisbane since January 2, but are now elsewhere in the state, to self-isolate.

"You isolate yourself for those three days," she said.

"If you are a local resident but have gone off holidaying on the Gold Coast or Sunshine Coast or Cairns, please stay where you are for three days and do not move around your area."

Further restrictions, fines to be issued

For the next three days, funerals will be limited to 20 people and weddings 10 people.

Dr Young also asked people to not go to any non-essential businesses like hairdressers, nail salons, cinemas and gyms.

Weekend sport has also been called off.

"We need to find every single case now," Dr Young said.

"Until we've found all those people, we can't relax." 

Police Commissioner Katarina Carroll said people needed to take the restrictions over the next few days "very, very seriously".

She said extra police resources would be diverted to help manage the lockdown and people would be fined $200 for not wearing a mask.

"If there is blatant disregard of the directives we will be ensuring compliance," she said.

"We will be conducting additional patrols, random intercepts, and making sure everyone is complying with the directives."

One-in-50 infected in the UK

Dr Young said the new strain was 70 per cent more contagious, currently one-in-50 people in the United Kingdom have COVID-19.

She said evidence coming out of the UK so far showed that the variant would not cause more severe disease nor increased mortality, nor would it affect the efficiency of the vaccines developed so far.

"UK health system can't manage the numbers," she said.

"So, if you can't manage the numbers, although this doesn't cause any more severe disease, if you can't provide oxygen and the basic care that those people need, then the consequences will be worse."