The NSW premier, Gladys Berejiklian, has backed hotel quarantine employees working across several hotels as authorities race to understand how a cleaner who worked at a quarantine hotel and a regular hotel in Sydney contracted Covid-19.
The state’s chief health officer, Dr Kerry Chant, also acknowledged on Thursday that interim public health advice meant thousands of commuters who caught trains and trams in Sydney should get tested immediately and self-isolate until updated advice is issued within 48 hours.
Health officials are worried about the potential spread of coronavirus given the cleaner travelled on public transport while potentially infectious.
Berejiklian said “at this stage” there was no reason to delay Monday’s easing of Covid-19 restrictions relating to larger venue and event capacities and the reopening of dancefloors. But the premier said she would not rule out altering her position if the health advice changed following further investigations.
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Urgent genomic testing will help authorities better understand how the woman contracted the virus. Chant said the cleaner didn’t come into direct contact with returned travellers so “there isn’t a smoking gun in terms of how we would say the transmission event happened”.
The cleaner developed symptoms on Saturday – mostly signs of fatigue – but was only tested on Wednesday night. After her positive result, her family also was tested late on Wednesday night, with all five members returning negative results. They will be required to isolate for 14 days.
Authorities believe the cleaner was infectious when she worked at the Ibis Hotel in Sydney’s Darling Harbour on 27 November – which is not a quarantine hotel – as well as when she later worked three shifts at the Novotel Sydney on Darling Harbour on 28-30 November. The hotels are next door to each other and are owned by the Accor group.
The Novotel is a police-guarded quarantine hotel for returned travellers. If a guest subsequently tests positive for Covid-19 they are sent to a health hotel managed by NSW Health.
Chant said “there’s a very narrow window when actually anyone is infectious in the police hotels”. She said once urgent genomic sequencing showed what strain of the virus the cleaner had authorities could “do the detective work” to understand how she became infected.
Colleagues who worked with the woman at the hotels and anyone who caught the same public transport services have been asked to get tested immediately and self-isolate.
Chant said the woman wore a mask on her more than hour-long daily commute from Minto to the Darling Harbour hotels.
Asked about Victorian rules preventing quarantine workers from working across more than one hotel – introduced following an inquiry into that state’s regime – Berejiklian said her position had not changed because workers would still be able to spread the virus in their social lives.
She said cases linked to hotel quarantine were more likely in New South Wales given the state’s 3,000 weekly cap on international arrivals, the largest number of any state.
Hotel quarantine workers were “as at risk of unknowingly spreading the disease if they go to a restaurant with lots of people [or] if they go to a wedding or other event”, the premier said.
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“If you do impose those things [limiting workers to one facility] … it is very difficult then to manage how you quarantine the quarantine workers. You can’t say to somebody who works in quarantine ‘You have no life except go home and come to work’.”
NSW police deputy commissioner Gary Worboys also defended the state’s quarantine system and noted it would have soon processed 100,000 people, with this week’s breach only the second authorities knew of.
NSW had recorded 26 consecutive days without a new case of Covid-19 prior to the cleaner’s positive result.
Before the new case was revealed, NSW Health called on residents in Sydney’s north-west to get tested even if they had only mild symptoms after wastewater analysis detected fragments of Covid-19 in sewage samples from Riverstone, Vineyard, Marsden Park, Shanes Park, Quakers Hill, Oakville, Box Hill, The Ponds, Rouse Hill, Nelson, Schofields and Colebee.