Adelaide's covid cluster explodes with 17 new cases after a hotel quarantine worker caught the virus from a traveller and infected their large family - and hundreds more could have been exposed
South Australia has confirmed another 17 cases of COVID-19 on Monday as an Adelaide hotel quarantine cluster threatens to explode out of control.
A worker at one of the city's quarantine hotels caught the deadly virus from an international traveller and then infected her large family.
Health officials are scrambling to trace contacts of the confirmed cases, which likely numbers in the hundreds, amid fears of a Melbourne-style lockdown.
South Australia chief public health officer said a cluster of cases in Parafield in Adelaide's north was growing at an alarming rate.
The list of potentially infected places over the weekend now include a prison, a hospital, a primary school, and aged care facility and a shopping centre, with more than 90 people already forced into quarantine.
Thomas More College in Adelaide's north and Hungry Jacks in Port Adelaide both announced they were shutting their doors on Monday morning to slow the spread of the virus.
The outbreak has prompted Western Australia to force all arrivals from South Australia since Saturday to self-quarantine for 14 days.
Health authorities said it's too early to tell if the crowds who went to the city's traditional Christmas Pageant at Adelaide Oval on Saturday have also been exposed.
Former WHO epidemiologist Professor Adrian Esterman said it appeared there had been a 'breakdown in systems' with the state's hotel quarantine program.
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Passengers who flew from Adelaide to Perth on Sunday were told to quarantine or go home. News of Adelaide's outbreak came as their plane was in mid-air. Pictured: a Qantas flight to Adelaide last month
The city's traditional Christmas Pageant at Adelaide Oval on Saturday have also been exposed although it is too early to tell at this stage, authorities have said
Travellers pictured at Adelaide airport on Saturday. South Australians' travel plans have been thrown into chaos by an outbreak that prompted WA to change its border rules on Sunday
'Many hotels should've been secure. But my understanding is that people weren't tested on a regular basis,' Mr Esterman said.
'SA Health have now ordered that all people working at the hotels be tested weekly -I'm surprised this wasn't happening before now.'
He said South Australia risked a Victorian-style outbreak if infections weren't kept under control in the coming days.
News of the cluster sparked an immediate reaction to control the outbreak, having learned from the wave of illness which swept through Melbourne in past months.
A planeload of passengers from Adelaide who landed at Perth airport just one day after border rules were relaxed were told to quarantine for 14 days or go home.
People about to depart Adelaide for Perth on Sunday were told they too would be required to quarantine for two weeks if they went ahead with their trips.
SA Health authorities believe the outbreak started when a worker at Peppers Hotel quarantine in Adelaide's CBD brought the virus home.
The couple, a woman in her 50s and a man in his 60s, then gave it to an 80-year-old woman who was the mother of one of them.
SA Health authorities believe the outbreak started when a worker at Peppers Hotel's quarantine facility in Adelaide's CBD brought the virus home. Hotel is pictured
The elderly woman visited the Parafield Plaza Asian supermarket between 10:30am and 11:30am on Thursday without knowing she was infectious, potentially spreading the virus.
On Friday night she sought treatment at Lyell McEwin Hospital in Adelaide's north where she was diagnosed with coronavirus on Saturday.
About 90 people who were in the hospital's emergency department between 5:30pm on Friday and 4:00am on Saturday have been ordered into quarantine.
The Lyell McEwin Hospital in Adelaide's north where a woman in her 80s was diagnosed. More than 90 staff and patients who were there at the same time in Emergency are in quarantine
Medical staff at an Adelaide coronavirus testing clinic in September. Adelaide's spiralling outbreak is worrying health authorities
South Australia's chief public health officer Professor Nicola Spurrier told reporters on Sunday that the infected trio have a 'very large family'.
Four close contacts have since showed symptoms and are awaiting coronavirus test results.
One of the family members worked at the Yatala Labour Prison - the city's biggest jail - in the northern suburbs and tested positive on Sunday.
A rapid-response team is helping contact tracers track the prison exposure, however it is not yet known when the employee was last at the prison or whether they had contact with the prisoners.
ADELAIDE'S COVID-19 OUTBREAK - WHAT WE KNOW SO FAR
A worker at the Peppers Hotel in the Adelaide CBD is believed to have caught the virus from an international traveller and then infected her large family.
The couple - a woman in her 50s and a man in his 60s then gave it to an 80-year-old woman, who is one of their mothers.
Elderly woman visited the Parafield Plaza Asian supermarket between 10:30am and 11:30am on Thursday without knowing she was infectious.
Growth in the Parafield cluster led to 17 new cases of the virus being confirmed in South Australia on Monday.
SA Correctional Services chief executive David Brown confirmed the case and said a female prisoner from a different jail had also been affected as she had been at the Lyell McEwin Hospital emergency department during the high-risk hours, ABC News reported.
Less than an hour after the prison case was announced, a primary school in Adelaide's north said it would have to close on Monday.
The Mawson Lakes Primary School and Preschool said it would shut for a deep clean after a student was found to be a 'close contact' of one of the infected person.
Professor Spurrier said it was too early to say whether people at the Adelaide Oval Christmas Pageant on Saturday had also been exposed.
She warned more people were likely to be infected.
'I am absolutely warning South Australians: This is a wake-up call — if you have respiratory symptoms, you've got to get tested,' she said on Sunday.
Professor Nicola Spurrier, South Australia's Chief Public Health Officer, pictured in May
The spiralling cluster is the first community transmission South Australia has seen in seven months - since April 15.
The emergency comes one day after Western Australia opened its borders to no-quarantine arrivals from South Australia.
It prompted West Australian authorities to snap their border rules back up for South Australian travellers after an emergency meeting on Sunday.
The tough restrictions had only been eased for one day, and the change caused havoc for hundreds of South Australians who crossed the border on Saturday and Sunday.
A plane load of passengers from Adelaide who landed at 3.22pm at Perth Airport on Sunday were told they have to quarantine for two weeks or return on a flight home to Adelaide on Monday.
The news of the coronavirus outbreak had broken while they were still in mid-air.
The 151 Qantas passengers had been expecting to land without restriction as Western Australian eased its rules at 12.01am on Saturday so that residents from all states and territories except NSW and Victoria could enter without quarantining for two weeks.
Instead, they were met at the airport by nurses, health officials, Australian Defence Force personnel and police carrying personnel protective equipment.
Mawson Lakes Primary School and Preschool in Adelaide's north is closed for cleaning on Monday after a student was found to be a close contact of an infected person
More than 500 passengers from Adelaide flights are expected to land at Perth Airport this weekend, with 289 already arriving on Saturday and a further 266 people on two more Qantas flights on Sunday night.
Those who arrived on Saturday by either air or road before the new emergency restrictions came into force will be contacted and asked to self-isolate for 14 days and take a coronavirus test on day 11.
South Australian travellers are now subjected to the same quarantine and testing requirements as those from NSW and Victoria.