BRISBANE, Australia (AP) — Australia is nearly halving the number of passengers allowed to arrive by plane in a bid to prevent the spread of a highly contagious variant of the coronavirus first identified in Britain.

A cleaner at a Brisbane quarantine hotel diagnosed with COVID-19 on Wednesday is the first person infected with the variant found in the Australian community. Other cases have been detected among travelers while in hotel quarantine, where there is little risk of community spread.

Prime Minister Scott Morrison said state leaders had agreed that international arrivals to New South Wales, Queensland and Western Australia state airports would be halved until Feb. 15. Arrivals at Victoria were already relatively low and would remain unchanged.

Quarantine workers would be tested for the virus daily.

Authorities in Brisbane are locking Australia’s third-most populous city down for three days beginning Friday evening to contain the spread.

Australian Chief Health Officer Paul Kelly said anyone who had been in Brisbane since Jan. 2 should also isolate.

“Our main issue is to keep Australians safe and to really make sure that this particular strain is not the one that becomes circulating in Australia,” Kelly said. “The reason is because it will be much more difficult to control.”

Masks will also become compulsory for the first time in Brisbane and some surrounding municipalities, the Queensland state government said.

The state Chief Health Officer Jeannette Young noted the more contagious nature of the variant had made the U.K. outbreak more difficult to control. “So we need to act really, really fast. We need to find every single case now,” Young added.

The woman's diagnosis ends almost four months of no locally acquired infections in Queensland.

In other developments in the Asia-Pacific region:

— A state of emergency took effect Friday in and around Tokyo as coronavirus cases surge. Japanese Prime Minister Yoshihide Suga issued the declaration Thursday. It lasts until Feb. 7, and asks restaurants and bars to close at 8 p.m. and people to stay home and not mingle in crowds. The declaration carries no penalties. But it works as a strong request while Japan juggles to keep its economy going. Shopping malls and schools will remain open. Movie theaters, museums and other events will be asked to reduce attendance. Places that defy the request will be publicized on a list, while those that comply will be eligible for aid, according to officials. Suga also promised more aid for hospitals treating COVID-19 patients. The Japanese military is ready to help, and efforts are underway to get a vaccine approved and delivered, he added.