“If in doubt, wear a mask” she said. The mask rule will remain until 1am on January 22.

Palaszczuk confirmed Greater Brisbane had avoided the community transmission of COVID-19 in the wake of two people being diagnosed with the more contagious UK strain.

With more than 18,000 tests conducted over the last 24 hours, and a high level of compliance with the lockdown, the only new COVID-19 cases recorded were in four people – including two flight crew members – arriving from the United Arab Emirates.

An investigation into how a hotel quarantine cleaner contracted the UK strain is ongoing, and hundreds of potential contacts have come forward to be tested. A visitor to Maleny sparked a broader contact tracing effort.

Palaszczuk thanked Queenslanders for their “big sacrifice” over the weekend and said the lockdown would end at 6pm. She was “absolutely relieved” there had been no new cases, having feared a rampant outbreak.

“This is a highly contagious strain, 70 per cent more contagious, and we don’t want to see that in our community,” Palaszczuk said.

Chief Health Officer Dr Jeannette Young said that for the next 10 days, distancing requirements would be in place in venues and Queensland would follow the lead of NSW and Victoria by mandating the use of masks in certain circumstances in public.

“We still do have to be on heightened alert,” Young said, concerned that not everyone who potentially came into contact with the two infected people had come forward to be tested.

“Masks are quite a game-changer.”

Until 1am on January 22, people in Greater Brisbane will be required to carry masks and wear them in indoor places including shopping centres and supermarkets, gyms, workplaces where people cannot socially distance and where it is safe, places of worship, libraries, public transport, taxis and ride share vehicles. This will extend to any travel outside of Greater Brisbane.

The Queensland Police Service is seeking the legal authority to fine people $200 for failing to wear a mask. Over the weekend, police took a more collaborative approach, distributing more than 1,000 masks to people who were not covered up.

The cricket Test between Australia and India on Friday will be subject to the new restrictions, although spectators will be allowed to remove their masks while seated.

“The Gabba will be filled to half the capacity and masks are mandatory for entry, and leaving, and for moving around the stadium,” Young said.

Social distancing requirements will see indoor venues restricted to one person per four square metres, outdoor venues to one person per two square metres, with seated eating and drinking only and no dancing except for weddings.

There will be a limit of 20 people for any organised gatherings in homes or public spaces, and up to 100 for weddings and funerals.

Restrictions on visits to hospitals, aged care, disability accommodation and prisons remain.

The UK strain has prompted Australia to limit the number of returning travellers, following Queensland’s decision to require weekly testing of all hotel quarantine staff.

Palaszczuk said she was comfortable with the quarantine of the latest infected arrivals and it was not yet known whether any had the UK strain, although two had been in the UK.

Palaszczuk said the lockdown was “definitely not an over-reaction” and well-supported by experts and the general public. Asked if a new case of COVID-19 could put Greater Brisbane back into lockdown, Palaszczuk said “it depends if it’s from this UK variant”.

“This is a whole new ball game,” Palaszczuk said, referring to the need for further discussions at a state and national level.

A teenager has been fined for attempting to travel to the Gold Coast during the lockdown without a valid reason, while a man also came to the attention of police after failing to wear a mask – or a helmet – while riding a motorcycle.