There are "positive signs" in the Covid outbreak response but "mystery cases" still pose a challenge, says Associate Health Minister Ayesha Verrall - amid calls from some experts that lockdown restrictions may need to be tightened.
Health authorities were working to understand all the positive cases and how they were linked, Verrall told Newstalk ZB's Mike Hosking today. There are currently 53 cases that are unlinked.
Verrall told TVNZ it was good to see only a slight rise in cases in successive days - 82 on Saturday and 83 on Sunday. About half of yesterday's 83 new cases were all household contacts. "All of those are positive signs that level four is working."
Auckland University associate professor Shaun Hendy said if mystery cases couldn't be connected to any known cluster then it would be a concern. However, at this stage it appeared to be a lag in getting information rather than an unsettling development in the outbreak.
• Thursday, August 26, between 7.30am and 6pm • Friday, August 27, between 7.30am and 6pm • Saturday, August 28, between 7.30am and 3pm
Why South Island should move to level 2 slowly - expert
University of Canterbury Covid-19 modeller Professor Michael Plank told RNZ that if lockdown proved to be effective, it was possible numbers could come down to 10 a day by the "latter part" of September.
He said it was too risky for the South Island to drop down to level 2 too quickly as it could cause a leak in Auckland and thereby create an "explosive outbreak". With the rest of New Zealand in L3, it meant there was a safety net.
Cabinet meets today to confirm the extension of level 4 for Auckland and Northland from 11.59pm Tuesday. It is expected Northland will remain at level 4 for at least another week and Auckland potentially for two more weeks. The rest of the country moves to level 3 from Wednesday.
Plank said it did appear as though the Delta outbreak was plateauing but it should become clearer over the next 48 hours. It was "taking a bit longer to get this outbreak under control than other outbreaks".
"The week ahead is really the crunch week in terms of whether we start to see the numbers come down."
Meanwhile, Verrall revealed health officials were now looking at the possibility and research surrounding offering people two different vaccine jabs.
Hosking put to her comments from Professor Graham Le Gros, of the Malaghan Institute, that results show people are better protected when they get two different vaccine shots - for example, an AstraZeneca followed by a Pfizer shot, Verrall said: "We have asked officials to look at that."
"We have a portfolio that includes AstraZeneca. So we do have that option should we need to use it in combination with Pfizer after the two-dose series that everyone's got."
The Herald revealed yesterday that the Government may "borrow" vaccines from overseas early in order to avoid shortages - with the possibility some might be brands other than Pfizer.
Level 4.5? Experts want to see tightening of lockdown
Despite the minister's comments this morning, experts are calling for level 4 restrictions to be tightened as case numbers continue to rise during lockdown - or risk the outbreak dragging on for many weeks.
These measures could include cutting the numbers of essential workers in the workplace, improving protective barriers and increasing mask-wearing - particularly in indoor areas - to combat the highly infectious aerosol-spread virus.
The total number of cases in this outbreak now stands at 511, with 83 new cases announced yesterday and 82 on Saturday - the highest two tallies of the outbreak, so far.
Naval base in lockdown
A New Zealand Defence Force spokesperson said the Naval Base and the Narrow Neck Accommodation and Training facility in Auckland's Devonport returned a positive result late on Wednesday 25 August following wastewater sampling on Monday 23 August.
The facility was put into lockdown to restrict access to and from it.
All personnel at Narrow Neck had been isolating at Level 4 and had been tested for Covid on the advice of the Auckland Regional Public Health Service. They remain in isolation. \
A second wastewater test on Thursday 26 August returned a negative result.
The tests on 54 junior officers and ratings staying at the Narrow Neck facility have come back as negative and there are still waiting on eight.
"The Navy has called in personnel who were on reserve standby to replace personnel who were rostered to start a MIQF duty," the spokesperson said.
Director general of health Dr Ashley Bloomfield said authorities expected to see the high number of cases continue over the next few days - largely because of the large number of household contacts and more infectious nature of the Delta strain.
This was neither concerning nor unexpected, he said, but it would be worrying if we started seeing more cases in the community.
Of the 511 cases, 453 cases have been clearly epidemiologically-linked to another case or sub-cluster, while there are a further 58 cases for which links are yet to be fully established.
Importantly the "R", or reproductive, number of the virus had dropped below one, meaning each person on average was infecting less than one other person.
Epidemiologist Dr Michael Baker said it appeared the case numbers were beginning to plateau and it was good news the "R" number was dropping.
"It shows people in Auckland are doing what they need to do to stamp this out. We really got there in the nick of time with lockdown."
However, while not rising exponentially, case numbers were still high and would take a while to stamp out under current settings, Baker said.
"We want to get Auckland out of lockdown as soon as possible. But unless we can suppress transmission more it is looking like they could be at level four for many weeks more."
Importantly, Baker said any points of transmission needed to be closely examined and restrictions around them tightened up.
Baker said, unless key points of transmission were tightened in the areas where essential workers were working, Auckland's lockdown could drag on for weeks.
This could involve reassessing the definition of essential workers, and seeing if any could actually work from home instead.
Other measures would be recognising the aerosol nature of the virus, and tightening up indoor areas with mask use and barriers.
Outside of essential services there should also be close scrutiny of how cases have spread so the public are aware of why extra measures were required.
"If we want to keep the whole country understanding not just what but why, we need that information presented in a clear way."
Each day Baker said the ministry should be explaining as much as it can about how the latest cases have occurred, and what is being done to plug those gaps.
Dr Siouxsie Wiles said staff might need mandatory vaccinations and be required to wear N95 face masks if working in an area where it was impractical to keep windows or doors open or ventilation can't be retrofitted.
The microbiologist said physical distancing, perspex barriers and even low-grade face masks weren't good enough at stopping Covid-19 in some enclosed spaces.
University of Auckland Professor of Medicine Des Gorman agreed it looked like our Covid-19 cases were plateauing but everyone, including him, was just guessing.
Speaking to The AM Show this morning, Gorman said the current numbers were consistent with spread within homes. "I can't see any evidence that there is something dire or very worrying going on...the lockdown is almost certainly working."
Suggestions of a stronger level 4 and "doom and gloom predictions" about being locked down until Christmas were unhelpful, he said. If there was no reward for vaccination or staying home, people would be disincentivised to get the jab or follow the rules.
Plans to double the number of contact tracers showed the Government was ill-prepared for the outbreak - but it was "better late than never", he said. "Our contact tracing capacity was nowhere near good enough."
However level 4 lockdown would make up for the "deficiencies in our public health measures".
Gorman did not think lockdowns would be tenable in the future after most people had been vaccinated. The country would run out of money and goodwill if there were frequent lockdowns into 2022 and 2023.
Asked whether he was concerned about people potentially spreading the virus while exercising, Gorman said he was at Cheltenham Beach yesterday, and although it was busy everyone was socially distancing and wearing a mask.
It was important that people were able to exercise and maintain their mental health, he said.
He was concerned mental health and diseases like cancer would be deferred by the lockdown.
University of Auckland Covid-19 modeller Shaun Hendy said with the Delta variant, a lot of people are testing positive after a family member or household member has tested positive.
Speaking to Newstalk ZB's Mike Hosking this morning, he wanted to understand why the Bluetooth feature on the Covid tracer app was not being used. "I'm a little bit surprised by that."
"I do think we need to be taking this lockdown very seriously," he said, adding that it was not inconceivable that we could see alert levels coming down.
Put to him that it looked as if Auckland, at least, would stay in alert level 4 lockdown for a few more weeks, Hendy said it was still difficult to tell at this stage.
"If we start to see numbers dropping sharply this week - so towards the end of the week, if numbers start coming down - then two weeks is not inconceivable.
"We did see the move to alert level 3 in Wellington with cases because they had those cases contained."
"The levels of testing that we've done in this outbreak have been phenomenal and they will give the Government the confidence to move once they see those numbers coming right down."
Hendy said it was always a risk when essential workers came together.
The Ministry of Health has been unable to provide clear data about the nature of the new cases during lockdown, importantly how many have been infected within their household bubbles and how many infected in the community. The Herald has been asking for this information since lockdown began.
When asked on Sunday for these figures, Ardern was not able to give a clear answer but said there were 53 "mystery cases".
She said more than 75 per cent of the positive cases reported yesterday were contacts of known cases and more than half of all cases yesterday were household cases, showing how infectious Delta was.
A total of 25 people had exposure events outside of the household and there tended to be essential work sites that were not customer facing.
There had also been transmission at four essential workplaces between staff members in non-public-facing roles.
Overall there were at least 73 essential workers infected during this outbreak, though it was not clear how many had been infected since lockdown began and how many had passed on the virus to others.
In New South Wales, experiencing the worst outbreak in Australia with more than 1200 cases and six deaths on Sunday, many Delta cases spread through essential workers.
Ardern said they were looking closely at the rules around essential workers.
"We've asked for further analysis of the nature of these workplaces, so we can assess whether our level 4 rules on who is operating is being adhered to, and whether our public health protocols for those businesses that are operating are fit for purpose.
"This may not be a problem with the rules, say, on the factory floor but what is happening perhaps before or after shifts, or even during break times.
"We're looking at all of this in more detail, if we need to tighten up our restrictions further, we will."
Ardern has also acknowledged the ongoing positive cases, combined with lockdown, could be hugely unsettling, impacting on mental health and stressed that support was available for anyone who needed it.
"It was okay to feel frustrated and there were places to go for help."
She said there had been a spike in calls to Youthline since the last lockdowns and an additional $1m would be put into increasing support, particularly for rangatahi in Auckland and Northland.
There was also targeted assistance for Pacific communities, which had borne the brunt of the outbreak so far, she said, and assistance for those struggling to access food.
An extra $7m was announced yesterday to assist organisations with things like distributing food parcels and welfare packages.
Meanwhile, Deputy Prime Minister Grant Robertson said New Zealand could take over other OECD countries by the end of this year if Kiwis keep up the level of vaccination rates the Government has seen so far this lockdown.
There were nearly 80,000 people vaccinated on Saturday, and over 90,000 the day before.
Robertson said New Zealand wouldn't run out of vaccine. "We won't run out of vaccine. We have orders coming and by the end of October we will have everything in terms of the vaccination that we need."
Ayesha Verrall told TVNZ it was "absolutely unacceptable" that people were being asked in Rotorua for their passports before their vaccinations.
Apologising to the people involved, she said immigration status had nothing to do with getting vaccinated.
"You don't need anything. Just a name and date of birth to link into the health information system. There is absolutely no need for a passport. This should not happen."
And on RNZ, Verrall said: "I don't think there's going to be a good enough reason to be asking for someone's passport."
People didn't need a passport to access testing, contact tracing or a vaccination. "We want everyone to be tested despite your immigration status."
"We have communicated with the DHB that that is not our expectation ... everyone should be able to access the care and public health treatment that they need."