About 5000 people who have recently arrived from Victoria must take all possible precautions to avoid a Covid-19 community outbreak in New Zealand too, a disease modeller has warned.
Photo: AFP
The Australian state of Victoria went back into lockdown at 2am today in response to the latest Covid-19 outbreak, involving a highly infectious variant.
Some of those in Melbourne who caught the new variant passed it on just over a day after catching it. Usually transmission takes five to six days.
That means to cut off any risk of it spreading here via the trans-Tasman quarantine-free travel bubble it was vital risk-management rules were followed stringently and straight away, said Professor Shaun Hendy, director of Te Pūnaha Matatini, the University of Auckland Centre of Research Excellence for Complex Systems.
The list of exposure sites across Victoria reached more than 100 locations.
And the 5000 people who have arrived here from the state since the start of the outbreak were being told to isolate until they can get tested, and receive a negative result.
Officials started contacting those affected last night and that will continue today. The quarantine free travel with the state is on hold until Friday next week.
The likelihood of the new variant having already travelled here from Victoria was considered low risk, but a real risk nonetheless, Hendy told Morning Report.
New Zealand was now dependant on those who had been in Victoria taking action to keep the rest of the country safe, he added.
"We've seen how quickly this cluster has grown ... and it's really outpaced their contact tracing, it just shows how much more difficult the strains that we're dealing with this year are than where we were last year," the Covid-19 modeller said.
"We could see a case or two, we can't rule that out. What we do need to do, with these new strains, is move much more quickly and stick to those rules, and try and be as compliant as we can, staying at home and making sure that you get that test."
Professor Shaun Hendy. Photo: supplied
If recent arrivals do that, any cases here as a result of the Victorian cluster should be identified within a week, he said.
"We can't operate these travel bubbles without people taking some responsibility. If you travel to Australia then you do need to accept that there is a risk that this sort of situation could occur.
"We have to rely on people being responsible, paying attention to the news, and keeping an eye on those locations of interest that are coming up in Melbourne, and just acting and behaving responsibly."
"We know, looking back at last year, that people were pretty good at isolating at home." - Professor Shaun Hendy
Hendy said he was confident most people would act responsibly.
"We know, looking back at last year, that people were pretty good at isolating at home." But he cautioned that protocols like using the QR app scanning, were not being used as much as before.
"We know that Kiwis do tend to get complacent when we go for a long period of time without Covid here," he said.
Morrison's visit to NZ hangs in the balance
Australian Prime Minister Scott Morrison was scheduled to arrive in New Zealand on Sunday for a much-anticipated two-day visit. But on 20 May, Morrison was in Pakenham, a suburb of Melbourne.
University of Auckland Politics professor Jennifer Curtin told Morning Report that if he did proceed with the visit to Aotearoa it could be a bad look to Australian voters.
"There are several risks that Morrison is going to face with this. Perhaps New Zealand wants this visit more than Australia, or needs it because the plan was to showcase the value of the travel bubble - tourism in Queenstown.
"He's suffered setbacks in the past by taking overseas trips at a time when at home things are vulnerable ... we can think about the bush fires and his trip to Hawaii. He wants to go to an election later this year, Victoria is in a state that is still high risk with this Covid outbreak".
Curtin said Morrison also faced potential backlash because of the "slowness" of the vaccine rollout.
"If he comes to New Zealand and we make a special health order variation just for him, it might work for us. But it's really not clear yet whether Australian voters will see it is a good look."
"Perhaps, New Zealand wants this visit more than Australia, or needs it" - University of Auckland Politics professor, Jennifer Curtin
In Melbourne, Deakin University public health expert professor Catherine Bennett said the lockdown had resulted in an uptake of the Covid-19 vaccine.
"In the first day when this was starting to be clear that there was a community transmission event we saw a doubling of the people that were stepping up for vaccination ... the call centres were overwhelmed with people trying to book in."
Going into winter, Covid-19 symptoms could become disguised as cold and flu symptoms, she told Morning Report.
"It's hard to tell in the first couple of days because you're looking backwards, you're going back to cases that have been in the community, household and been infectious for a number of days before being discovered.
"The good news is that we haven't had any cases that cannot be directly linked either through a workplace of one of the cases or it seems all the rest are linked to the family clusters."
She said despite many exposure sites, "passing contacts" had not tested positive.
"We're still learning about this variant associated with India the B.1.617, we know it's more infectious, we know it looks something like the B.1.1.7 UK-associated strain. The first close contacts we had about 15 percent return a positive result, that's what you'd normally see."
"The good news is that we haven't had any cases that cannot be directly linked" - Deakin University public health expert professor Catherine Bennett
Purpose-built quarantine facilities
University of Melbourne head of school of population and global health Dr Nancy Baxter said purpose-built quarantine facilities would be would be a smart investment in both Australia and New Zealand.
The strain of coronavirus circulating in Melbourne was more infections and also seemed to be passed on very rapidly, taking only one day between contracting the variant to transmitting it, Baxter said.
"There's almost no time to get on top of this, so that's part of the reason behind having this lockdown."
"We really need to think about how we move to more purpose-fit quarantine facilities, particularly for people coming from high-risk countries or unvaccinated people" - Dr Nancy Baxter
Baxter said the first case in the outbreak, who was infected in hotel quarantine in South Australia, seemed to have come into contact with the virus circulating the air of the hotel corridor.
Purpose built facilities such as Australia's Howard Springs, with separate cabin accommodation and no corridors, have a good chance of lowering the risk, she said.
"We're likely going to have to have quarantine for some time and the way it's looking these variants are only going to become more infections and more easily transmittable in the air.
"To me it would make sense to start building them in New Zealand as well as Australia.
"You could have a pretty swank purpose-built facility for cheaper than it's going to be to shut down Melbourne for seven days."