August 19 2021
There are now 21 Delta Covid-19 cases in Auckland, including two in hospital.
ANALYSIS:
Still no source case, total cases hitting 10 (as of this morning), and potential super-spreader venues including a church service, Avondale College, an AUT lecture theatre, and several cafes and bars including SkyCity Casino.
That means more cases are inevitable, potentially in the hundreds, before we start to see the impact of the lockdown coming through in the case numbers next week.
So no light at the end of the lockdown tunnel yet.
The cases are so far all part of the same transmission chain, except for a woman in her 60s with a connection to the border.
She was confirmed this morning as Air NZ cabin crew picked up during routine testing.
No source case is one of the assumptions in the modelling done by Professor Shaun Hendy's team, which suggests between 50 and 120 cases already circulating in the community when the Devonport case tested positive.
The estimates assume an average of two links between the index case and him.
That could also align with the timeline in the locations of interest, which, as of last night, dated back to August 3.
We may know more about the likely number of links once the genomic sequencing results come back from the MIQ cases from New South Wales since August 9.
A good sign would be a match, which would indicate a small window of time between the index case and the Devonport tradie, who became infectious on August 12.
No match could mean someone carried Delta across the Tasman in the previous weeks after leaving Covid-ravaged NSW so they could fly here from a different state, thereby avoiding MIQ.
Looking for this person among thousands of travellers would be needle-in-haystack stuff, but still worthwhile because it could reveal an index case that might still be infectious.
The number of possible cases downstream of the Devonport case is unnerving, given the number of super-spreader venues.
Many of them may be unvaccinated people under 30, as in some of the current cases.
It highlights why Prime Minister Jacinda Ardern included young adults as one of the key groups that needed high vaccination coverage when she announced her border reopening plan last week.
They are more likely to have social calendars that could spread the virus in a hurry.
The Government could start surge vaccinating young adults in Auckland and the Coromandel, but immunity isn't instant, so it wouldn't limit any spread unless the outbreak dragged on for several weeks.
Ardern has already deployed the best tool she has - level 4 lockdown - to limit downstream spread.
It has now been enhanced with mandatory mask-wearing at essentially every indoor venue outside your home.
Prime Minister Jacinda Ardern has made alert level 4 stricter with mandatory mask-wearing in certain circumstances. Photo / Mark Mitchell
There may not be much left in Ardern's toolkit to make the lockdown any stricter.
Mandating physical distancing is likely a step too far, while mandatory scanning of QR codes is more useful at alert levels where people aren't already staying at home.
And she is hardly about to roll out the military to make sure the rules are followed.
Her next big dilemma may well be whether to ease restrictions for any regions without any known cases at the end of the three-day timeline for level 4.
By then she - and we - will be hoping that testing around the country will provide a far fuller picture of what we are facing.