Jacinda Ardern and Winston Peters have been singing from very different song-sheets when it comes to moving New Zealand to alert level 1. Photo / Pool
Jacinda Ardern and Winston Peters have been singing from very different song-sheets when it comes to moving New Zealand to alert level 1. Photo / Pool
ANALYSIS
For a moment, it seemed like a mutiny led by the Deputy PM was on when Winston Peters came out swinging last week with a push for alert level 1.
It had actually been flagged the previous day when Jacinda Ardern had said NZ First ministers haddisagreed with staying at level 2 - but Peters' sentiment still resonated with the public and in the corridors of power.
The Prime Minister has marked June 22 as the last day Cabinet will consider moving to level 1, but pressure to bring that day forward will grow as the days of no new reported cases stretch into double digits.
And not only for the economic or political reasons. A health argument could be mounted to move to level 1 as soon as next week.
There is broad consensus (with some slight variations) among public health experts that 28 days of no new cases are needed before Covid-19 can be said to be eliminated.
This is also in line with the Health Ministry's own elimination strategy.
The need for this breathing space is clear enough for eminent epidemiologist Sir David Skegg to dismiss any cries for level 1 as "ignorant".
Just because there are no new detected cases doesn't mean there are no cases. As has happened overseas, all it takes is for one Covid-carrying person to be in one crowd to spark dozens of branches of new transmission.
If that happened, some of those branches may not show up in testing for weeks because Covid-carriers can be infectious but asymptomatic for up to 10 days.
The likelihood of any undetected cases shrinks as zero-case days continue, and after 28 days - if testing rates remain high - an "eliminated" banner can be confidently hoisted.
(Given that elimination is an ongoing process, not a point in time, the banner can also be floored very quickly.)
So when does the clock start ticking on the 28 days?
University of Otago public health experts have cited two key questions to inform an answer:
• What was the date of the last newly notified case of transmission in New Zealand?
• When was the most recent case still infectious while out in the community? This could be when they went into isolation, came out of isolation, or if or when they tested negative.
You'd think the clock would start from May 22, the last time the Ministry of Health reported a case in its daily update, or even on the day that person comes out of isolation.
That case was an Auckland woman in her 50s - the country's only remaining active case - linked to the St Margaret's rest home cluster.
But she was first reported as a suspected case on May 1, and has been in isolation - with minimal chances of infecting anyone - since the start of the lockdown in March. Her case was only reported on May 22 because she had tested positive the previous day.
The most recent new case was first reported on May 15: A boy aged between 1 and 4 linked to the Rosewood rest home cluster in Christchurch.
The next most recent case was on May 14: A female student at Marist College who was tested when students were getting ready to return to school. She had symptoms in March and, having previously tested negative, is considered a "weak positive".
The next previous ones were on May 10: Two Waitākere Hospital nurses and a woman who flew in from France in the middle of March.
Who is the most recent infectious case: A woman isolated since March, a young Christchurch boy, a Marist student with no recent symptoms, or nurses linked to St Margaret's rest home (pictured)?
So here are four potential start dates:
• May 22 or later - the Auckland woman is still an active case (meaning she has had symptoms in the past 48 hours and may still be infectious)
• May 15 - the Christchurch boy is the most recent infectious case because the Auckland woman has been in isolation since March
• May 14 - the Marist girl is the most recent infectious case because young children are relatively non-infectious; early childhood learning centres were allowed open under level 3 on that basis
• May 10 - the Waitākere nurses are the most recent infectious cases because the Marist girl has had no recent symptoms and is a "weak" positive
Cabinet's D-Day to consider if the country is ready to move to level 1 makes perfect sense. June 22 is at least 28 days from all of the above start dates.
But Ardern has given herself some wriggle room to bring D-Day forward.
Cabinet is meeting tomorrow, but is not meant to consider alert level settings until June 8. On that day, it will have been 29 days since May 10.
The elements in the D-Day equation
Health chief Ashley Bloomfield's advice to Cabinet will factor in the biggest risk of triggering a second wave: Mixing and mingling.
Two dates should be flagged here: May 21, when bars reopened, and May 29, when gatherings of up to 100 people were allowed.
It takes 10 to 14 days for changes in the lockdown rules to start showing up in testing data.
That means any new cases that might have sprung from a reopened bar should start to be reflected in the data from now, and by June 8 Cabinet should have an idea if the first larger gatherings might have triggered any new chains of transmission.
(A very precautionary approach would be to wait to see testing data two weeks from today, when large, tightly-packed crowds - about 4000 in Auckland and 500 in Wellington - turned up around the country to protest against police brutality.)
Cabinet's decision will again be a judgment call on the likelihood of a second wave and the country's ability to contain one if one broke out.
Director general of health Ashley Bloomfield will provide advice for Cabinet's decision to move to level 1. Photo / Mark Tantrum
Community transmission appears to have been quashed. The most recent case was reported on April 30 but, according to Bloomfield, it's been about two months since targeted testing around such cases showed any onward transmission.
Testing, contact tracing capacity and control measures at the border are also ongoing factors in identifying and containing any new cases.
Much will depend on Bloomfield's advice, but Ardern has already shown a willingness to shun that advice when she allowed bars to reopen earlier than he had recommended.
She will also weigh up public willingness to comply with alert level rules.
A survey from Research New Zealand this weekend already showed cracks in compliance: A third of Kiwis said they were no longer observing physical distancing rules most or all of the time.
Public backing to move to level 1 will also grow if the Covid curve remains crushed, and as the economic fallout - 37,000 jobs were erased last month - becomes increasingly clear.
Political pressure on Ardern will also ramp up, and not just from National, Act and NZ First. There are those in Ardern's own party who are understood to have disagreed with last week's decision to stay at level 2.
And expect more noise from Peters as time marches on. It's a win-win strategy - unless a second wave breaks out.
If Ardern leaves D-Day at June 22, by then Peters will be on the side of substantial public, political and business opinion.
If she decrees that conditions are ripe for a move to level 1 on June 8 or any time before June 22, Peters will look like the driving force - regardless of whether that has any truth to it.
