LISTEN TO UPDATES ON NEWSTALK ZB:
* 148 cases, more than 460 events at 340 locations - hospital emergency department worker tests positive
* New locations of interest include three more supermarkets, two Farmers, another university campus
* 'NZ can't do that': Aussie PM Scott Morrison likens elimination strategy to living in a cave
* Claire Trevett: Is the PM chasing rainbows or can she stamp out Delta?
* Rising Black Caps star tests positive for Covid-19
* Readers' questions: Ask us anything on Covid
Experts are questioning whether there has been any "leakiness in lockdown", and are urging clarity on the details of the so-far 148 positive cases in New Zealand's Delta outbreak.
At the same time, they believe New Zealand's elimination strategy - and nationwide level-4 lockdown - remains the best option to combat Delta, despite criticism from Australian Prime Minister Scott Morrison who says the elimination strategy is "absurd" and like "living in a cave".
The Herald also revealed today that Auckland's surging Covid infections are causing a quarantine facility backlog, with infected people waiting more than 24 hours for admission.
Prime Minister Jacinda Ardern told Coast FM she wasn't "too fussed" by what the Australian PM had said and all the decisions made over the past 18 months were about New Zealand and not what other countries thought.
Ardern said New Zealand needed to have a good number of people vaccinated across all the regions and age groups.
"We can't live for lockdown forever and we don't intend to."
Ardern said there was a lot of discussion and debate around booster shots but not a clear conclusion on them yet.
"We are still in a place where there's still a lot of debate among the experts and immunologists about the booster shots."
But New Zealand was keeping its options open and keeping the conversation with the pharmaceutical companies if it did need them in the new year.
Ardern said even if they did move managed isolation facilities outside Auckland, a workforce was still required to look after the 4000 to 5000 people a fortnight who were in MIQ.
"So as you can imagine literally hundreds, thousands of people working to support those facilities so even if you move them out of a city you still require a huge workforce and they come from somewhere. That's why we vaccinate, we test frequently, we do everything to reduce down the risk."
She said work was being done to think about the role of managed isolation going forward and if they needed to change the way they used it.
Deputy Prime Minister Grant Robertson also rejected Morrison's comments, saying the elimination strategy had given New Zealand one of the strongest economic responses and one of the lowest mortality rates in the world.
"I just don't see it the way that Scott Morrison and others are presenting it and certainly every public health expert I speak to says that what we're doing right now is exactly the right strategy for New Zealand," Robertson told Newstalk ZB's Mike Hosking.
The number of Covid cases is predicted to rise dramatically in coming days with just half of the highest-risk contacts having returned their test results.
The vast majority of these cases were infected prior to lockdown, but the Government is also unable to yet confirm if the virus has been spreading under lockdown.
Director general of health Dr Ashley Bloomfield said "some" cases had been infected since lockdown began last Wednesday.
Most of these were close contacts of the cases, most in the same households, however he was unable to confirm if any had spread outside their bubbles, or if any close contacts were essential workers.
Experts are calling on the Government to identify and release this information to the public as soon as it can, given lockdown spread will be the key determinant of whether the outbreak is being brought under control.
Otago University epidemiologist Professor Michael Baker said it would be useful to see the Government classify cases as those that were in the community before lockdown, those that had been detected while at home, and those that were among essential workers still operating under alert level 4.
"What we really want to know is if there are any unsuspected cases occurring in the community that don't have a connection to cases reported now, which could suggest some leakiness in lockdown."
Fellow modeller Professor Shaun Hendy said they were now estimating the outbreak could swell to 1000 cases.
Robertson said hundreds of contact tracers were conscripted to bolster the permanent public health force - to help get tests done and results back as quickly as possible. He told Hosking that 600 were being trained up to meet the demand under Delta.
There was now a 48-hour timeframe to make contact with those affected.
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