Queensland will enforce a three-day lockdown in Brisbane from tonight, after a quarantine hotel worker tested positive for the more contagious variant of Covid-19 that has emerged in Britain.
"We know that the level of infection is very high in this particular variant. We have to act differently to what we had before. Any delay could see significant, if not catastrophic results," state Health Minister Yvette D'Ath told reporters.
The decision to temporarily shut down Australia's third-largest city came hours before a special national Cabinet meeting to consider a proposal from the country's expert medical panel to further tighten rules for international travellers.
Brisbane's more than 2 million residents must wear masks and can go outside only for one of four essential reasons - grocery shopping, work, exercise or medical treatment.
"If we do not do this now, it could end up being a 30-day lockdown," state Premier Annastacia Palaszczuk said.
Nationally, Australia will require all international travellers to test negative for Covid-19 before boarding flights to the country, Prime Minister Scott Morrison said.
Australia would also reduce by half the cap on international arrivals to some states until 15 February, he said.
Australia is on course to begin administering the first Covid-19 vaccines in February as it tries to contain the spread of infections in its largest cities of Sydney and Melbourne.
Queensland state reported no new local cases today, but the UK variant case has sparked fears of a wider outbreak. Victoria, the country's second-most populous state, reported no cases for the second straight day.
Australia has reported a total of just over 28,500 Covid-19 cases and 909 deaths since the pandemic began, with border closures and speedy tracking systems helping keep numbers relatively low.
New vaccine deal
Meanwhile, Australia has signed an advanced agreement to purchase 51 million doses of Novavax Inc's experimental Covid-19 vaccine, the company disclosed in a regulatory filing yesterday.
Australia will have the option to purchase up to an additional 10 million doses, with the initial doses expected to be delivered by mid-2021, the company said.
Novavax started a large late-stage study of the vaccine in the United States in December after delaying it twice due to issues in scaling up the manufacturing process.
The company lags behind other drugmakers in the global race for a Covid-19 vaccine, with shots from Pfizer, Moderna and AstraZeneca authorised in some countries.
Novavax in November signed an agreement in principle with the Australian government for a supply of 40 million doses of the vaccine and the latest deal replaces the earlier agreement.