Melbourne, Australia's second-largest city, entered a strict seven-day lockdown at midnight as a fast-moving Covid-19 outbreak prompted renewed border closures and appeared set to energise the nation's vaccination drive.
The state of Victoria imposed the lockdown after 12 new locally transmitted cases of Covid-19 were recorded yesterday, bringing the total number in the current cluster of community cases to 26.
But there are fears the outbreak could spread further as infected carriers are known to have visited almost 200 locations, including popular inner-city bars, restaurants, gyms, supermarkets, a cinema and at least two Australian Rules football matches.
More than 10,000 people have been deemed potential contacts and will now need to quarantine, or test and isolate.
Victoria's Acting Premier James Merlino said this particular viral strain is highly infectious and spreading fast.
"We are dealing with a highly infectious strain of the virus, a variant of concern, which is running faster than we have ever recorded," he said.
"We have seen overseas how difficult that movement can be to control… Unless something drastic happens, this will become increasingly uncontrollable."
Last year, Melbourne endured a 112-day lockdown - one of the longest in the world - to combat a second wave of Covid-19 infections.
The latest outbreak is believed to have originated with a man who was infected while undergoing quarantine in a hotel in Adelaide, and then travelled to Melbourne after his quarantine ended.
Victoria's short "circuit breaker" lockdown involves a ban on public gatherings and the closure of schools and most businesses.
People are allowed to leave their houses only for limited purposes such as shopping, medical reasons, exercise and to be vaccinated.
The outbreak prompted several states and territories, including Queensland and Western Australia, to close their borders to travellers from Victoria.
The most populous state, New South Wales, is requiring people who have been in Victoria to self-isolate for seven days.
"What is happening in Victoria is a wake-up call," said NSW Premier Gladys Berejiklian. "We don't know what is around the corner."
Melbourne's outbreak has prompted a sudden rush to vaccinate in Australia following growing concerns about the slow roll-out of Covid-19 vaccines and the apparent complacency around vaccination.
A public opinion poll published last week found that a large number of Australians were not planning to be vaccinated, apparently due to concerns about perceived health risks and a belief that the risk of infection in Australia is low.
The survey by the Sydney Morning Herald newspaper and Resolve Strategic found that 29 per cent of people were unlikely to be vaccinated, 13 per cent were fairly likely and 22 per cent were very or extremely likely, with the remainder including people who have been or were due to be vaccinated.
But Melbourne's outbreak this week has led to a sudden rush to vaccinate its residents.
The state had been allowing vaccinations for those aged 50 and over, but extended access to people aged 40 to 49 from today.
Massive queues suddenly formed yesterday at public access vaccination centres, and the state reported that a hotline to book doses crashed after it received 77,000 calls in just 15 minutes.
About 3.9 million doses have so far been administered across the nation's over 25 million residents.
Australia's Chief Medical Officer, Professor Paul Kelly, sent out a plea to Victorians during a media conference yesterday, saying: "Please get vaccinated."
