Australia's COVID-19 response committee is due to hold an emergency meeting on Monday as outbreaks of the highly contagious Delta variant across the country prompted a lockdown in Sydney and renewed restrictions elsewhere.
Around 18 million Australians, or around 70% of the population, are now under some form of lockdown or COVID-related restrictions as officials grapple with COVID-19 flare-ups in almost every state or territory.
"I think we are entering a new phase of this pandemic, with the more contagious Delta strain," federal Treasurer Josh Frydenberg told the Australian Broadcasting Corp on Monday, adding Australia was facing a "critical time" in its fight against COVID-19.
The national security committee, chaired by Prime Minister Scott Morrison, will be briefed by the country's chief medical officer later on Monday, Frydenberg said.
Sydney, Australia's most populous city, was plunged into a two-week lockdown over the weekend, while the northern city of Darwin entered a two-day shutdown, as officials grapple to contain the outbreaks.
Australia's Queensland state on Monday reintroduced mandatory masks and limited home gatherings in several areas, including state capital Brisbane, following a similar move by Western Australia officials for state capital Perth. Restrictions remain in place in Victoria state capital Melbourne and national capital Canberra.
A health alert was issued over the weekend for hundreds of passengers after an infected Virgin Australia cabin crew member worked on five different flights covering Brisbane, Melbourne and Gold Coast.
In Sydney, New South Wales state capital, dozens of venues including cafes, shopping centres and public transport routes scattered across the city have been added as virus-exposed locations.
The Darwin lockdown was prompted by the detection of the Delta variant of the virus in a fly-in, fly-out (FIFO) worker at a gold mine after he had left the facility.
Australia has so far fared much better than many other developed countries in tackling the spread of the coronavirus, with just over 30,450 cases and 910 deaths.
Lockdowns, tough social distancing rules and swift contact tracing have helped the country successfully suppress prior outbreaks but the fast moving Delta variant has alarmed health authorities.
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