A daily wrap of all the main developments in the Covid-19 Delta outbreak as New Zealand is plunged into lockdown for the fifth time. Video / Mark Mitchell / Brett Phibbs
ANALYSIS
There are many signs that it's safe enough to move the country outside Auckland to alert level 3 from Saturday.
But blind spots remain, the largest being the 7800 close contacts who have yet to be interviewed.
And there are almost 100 higher risk close contacts - including thosewho live or work with known cases - who are yet to be contacted.
Based on the proportion of those groups who have already tested positive, there could be as many as 40 cases among them.
They may have been dutifully isolating from anyone they live with and not leaving the house.
But it's possible that a handful of them have been doing the household grocery shopping, or going to work as essential workers simply brushing off a sniffle.
It would be surprising if Prime Minister Jacinda Ardern, whose cautious approach has served her - and us - well so far, was prepared to move any part of the country to level 3 without knowing more about these contacts.
All other signs seem to be positive in terms of encircling the outbreak, and Cabinet ministers will be hoping to see similar signs today as they did yesterday.
There is still no sign that there is any more than one chain of transmission, and while daily cases hit a new high yesterday, this was more or less the same number as the previous day.
All but two were in Auckland, and the two cases in Wellington were already in isolation.
There are signs the lockdown is working, with only three new locations of interest yesterday and none overnight. A further sign would be case numbers levelling off in coming days.
No positive wastewater results have emerged anywhere in the country where known cases haven't already been, and testing levels across communities remain high.
The Cabinet will mull over Auckland's fate on Monday, but Wellington may already be in the Covid clear.
The last location of interest posted in Wellington was from a whole week ago, and all of the cases in previous days were already in isolation.
And there's still a relatively small number of contacts in the South Island - at least 358, including 109 in the southern region, 193 in Canterbury, 36 in Nelson-Marlborough, 13 in South Canterbury and less than 10 on the West Coast.
As of 8am yesterday, there were 24,541 contacts in the national contact-tracing system - almost 14,000 of them in Auckland or Greater Wellington.
The key unknowns are whether there are new cases that have no connection to the existing cluster, or have been out and about in the community.
There is no evidence so far of post-lockdown transmission outside of anyone's bubble.
And only three cases so far have been customer-facing essential workers, including two nurses and one supermarket worker. Two of them were infected via their households rather than workplaces, and while the link between the cluster and the Middlemore nurse remains unclear, the risk is mitigated as they are fully vaccinated.
But there will be more cases among the almost 8000 close and close-plus contacts yet to be reached; so far 0.3 per cent of the close contacts and 15.6 per cent of the close-plus contacts have tested positive.
Some of them may have been close to one of the six sub-clusters, or have spent time in one of the 13 locations of interest where transmission appears to have occurred.
Prime Minister Jacinda Ardern and Covid-19 Response Minister Chris Hipkins will be part of Cabinet discussions about alert level changes outside of Auckland today. Photo / Mark Mitchell
Some of them may be essential workers, or might have been doing a household's grocery shopping.
Some may be part of a whole new chain of transmission that would then need to be encircled.
Contact tracing is also continuing at pace, and the Cabinet could decide to build a fuller picture by keeping level 4 over the weekend until more of the contacts can be interviewed.
The Cabinet could also make an in-principle decision to move non-Aucklanders to level 3 from Saturday on the condition that most of them will have been reached by then - with no red flags raised.
Delta has changed the equation, too. Previously level 3 was strict enough to see case numbers continue to shrink in an outbreak.
The tourist town of Queenstown is looking much like a ghost town after the Government put the country into a level 4 lockdown. Photo / George Heard
But experts have said repeatedly that level 3 - with bubbles expanded to include close family or caregivers, as well as weddings or funerals allowed for up to 10 people - can't contain Delta.
It's so contagious that it can jump from expanded bubble to expanded bubble at an R0 rate greater than one, meaning the transmission chain keeps growing.
Ardern won't sign off a level 3 move until she is very confident of zero Delta cases outside of Auckland that aren't already in isolation.
Her judgment on alert level decisions so far has almost always been on the money, but there is more at stake than how hard it is on communities to be given more freedom, only to be thrown back into level 4 soon afterwards.
Getting it wrong - as she did in February, when Auckland yoyo'ed between alert levels - would also carry the political cost of another black mark on her record.
