In Sydney, Australia, the pandemic feels like it is just getting started. The city is battling its worst covid-19 outbreak yet, which is being blamed on the highly contagious delta coronavirus variant and low vaccination rates.
Since early in the pandemic, Australia has tried to keep the coronavirus out altogether by banning international visitors, quarantining all Australians returning from overseas and rapidly locking down whenever covid-19 is detected in the community. This worked for a long period – in the first half of 2021, the country didn’t record a single death from locally acquired covid-19.
Then the delta variant arrived. A Sydney limousine driver who transported international aircrew was infected in mid-June, prompting stay-at-home orders to be introduced across greater Sydney on 26 June. The city’s lockdown is now in its eighth week – people can only leave home for reasons like buying food and essential work – but covid-19 cases and deaths are climbing.
Over 400 covid-19 cases are now being recorded daily in Sydney and the rest of the state of New South Wales. Eight deaths from the virus were recorded on 15 August – the state’s highest daily toll of the pandemic so far. The virus has also started to spread into other Australian states and territories.
There are several reasons why case numbers aren’t going down this time, even though the same lockdown, test, trace and isolate strategies that successfully contained previous outbreaks have been deployed, say experts.
One is the greater transmissibility of the delta variant compared with earlier variants, says Catherine Bennett at Deakin University in Melbourne. “Now, if the virus gets into a household, everyone gets infected, whereas last year probably only a third of people would,” she says.
The extreme contagiousness of the delta variant was highlighted when 45 of 50 people who attended a funeral in Sydney that breached the 10-person limit were infected with the virus. In another instance, a person appears to have been infected simply by walking past someone with the virus in a local shopping centre, as suggested by CCTV footage.
A race to vaccinate
The shorter incubation time of the delta variant is also making it harder for contact tracers to identify and isolate potentially infectious people before they can pass the virus on, says Bennett.
Finally, the virus has found its way into parts of Sydney that are home to high concentrations of people who can’t work from home, says Angela Webster at the University of Sydney. “They are doing caring work, warehouse work, cleaning, driving – things that are absolutely essential,” she says. The virus is spreading through workplaces, households and supermarkets in these areas, but “you can’t stop people doing essential work, living together, or buying food”, says Webster.
Since it is looking unlikely that Sydney will be able to contain this outbreak with lockdown measures alone, it is “now a race to vaccinate”, says Webster. Australia has been slow to vaccinate its population compared with other high-income nations, with only 26 per cent of people aged over 16 having received both jabs.
Australian government modelling suggests that lockdowns will no longer be necessary when 80 per cent of adults are fully vaccinated – a target it hopes to hit by the end of the year. Webster believes people in Sydney probably won’t be able to socialise in large groups or go to restaurants until next year.
“But there is hope,” she says. “Everyone here is very doom and gloom, but we are averting thousands of deaths with this lockdown and we know the vaccine will end it, it’s just going to take a while to get there.”
Meanwhile, New Zealand, which has also used strict measures to largely keep the pandemic under control, today brought in a nationwide lockdown following the detection of a new covid-19 case in Auckland.
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