What Prime Minister Jacinda Ardern told Cabinet before they agreed to lockdown New Zealand for four weeks has been revealed.
In a briefing to Cabinet on March 23, Ardern laid bare the dire situation New Zealand faced if it didn't move to alert level 3 then 4 as soon as possible.
The briefing was one of the hundreds of papers released online this afternoon.
At the time there were confirmed Covid-19 cases in 16 of the 20 district health boards and community transmission was "highly likely".
"If community transmission becomes widespread we will have lost the opportunity gained by closing the border. Once community transmission is established the number of cases will double every five days."
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It was critical New Zealand acted "decisively" to break the chain of community transmission to protect communities and prevent the health system from being overwhelmed, the paper said.
"New Zealand is at a tipping point. We have a short window of opportunity to take a trajectory more similar to Singapore and others who have taken an early and strong approach to containment, and avoid the trajectory of Europe, where community transmission has taken hold."
She recommended moving to level 3 "as soon as practicable" and a move to level 4 was inevitable in the near future if New Zealand was to break community transmission.
"We have no base level of immunity as humans have not previously been exposed to the novel coronavirus. There is no vaccine and no proven effective treatments.
"Because of this, the risk to the public health of New Zealanders is very high and is likely to remain so until scientists have found a vaccine or effective treatments. While scientific knowledge is increasing day by day, vaccines and treatments may be 12-18 months away."
Covid-19 was spreading rapidly across the world.
Even by taking a "flattening the curve" approach, our health system would still be overwhelmed and could face the high fatality rates seen in Italy. New Zealand needed to take a "suppression" strategy.
Until March 20, all cases were connected to overseas travel but two days later seven cases had no international travel history. The World Hereford Conference in Queenstown was of particular concern.
Community transmission was already happening or soon to be widespread. It was likely cases had been missed.
A study out of China showed most infections were undocumented and unidentified because most people had only experienced mild symptoms - if any at all.
"For Australia, the soft trigger for considering community transmission was the first confirmed case without an international travel history. Two weeks later, they saw a dramatic increase in cases. We are now at this same tipping point."
Officials warned a move to level 3 wouldn't be enough to break community transmission but New Zealand wasn't ready to move to level 4, the paper said.
"It will be difficult to bring the public with us (i.e. there may be confusion and concern caused by jumping straight from Level 2 to 4) and we are simply not ready to do so."
New Zealand needed the legislative powers to ensure enforcement and compliance, to work out implementation issues like defining essential services and economic and social support available.
To move to level 4, a State of Emergency would need to be declared as it was not clear "that the other powers in legislation are sufficient to allow the necessary actions".
Regulators would need to put in place communications, monitoring and compliance systems and if they weren't strict, people wouldn't comply.
They should "encourage voluntary compliance as a preference, but be prepared to warn, fine and prosecute".
"Not sufficiently addressing non-compliance would undermine the comprehensive behavioural change required."
But it would not be possible to list every single essential service so businesses and employers would need to make their own assessments and if in doubt, contact the Government.
The measures level 3 would require were "expensive, disruptive and inconvenient".
"They will mean real harm and have extremely significant social and economic implications for New Zealanders: people will become unemployed, be unable to pay their bills, go out of business, and there will be psychosocial impacts."
Those psychosocial impacts would have to be prioritised alongside the physical health response, the paper said.
• those who became unwell or were at high risk of becoming unwell would suffer mentally and the general population would have "significant distress" because of fear and anxiety of becoming infected
• at-risk populations had an increased psychosocial risk
• individuals or groups could be targeted by people "who are not well informed"
• homeless and rough sleepers were "in essence living in a vacuum" through not having access to updates through media and the Ministry of Health website
• family harm, sexual violence and child abuse were likely to increase
• older people would be removed from social situations and made up a significant proportion of volunteers
Māori were particularly at risk, the paper said.
"It is evident from previous pandemic responses that the business-as-usual model previously used preferentially benefited non-Māori and failed to protect whānau, hapū, iwi and Māori communities from the worst outcomes.
"Consideration to the specific needs of Māori, particularly equity and active protection, should be integral to the Governments response to Covid-19."
And Pacific families would need specific information to remind them to restrict gathering, keep children away from grandparents, there would be financial implications and churches couldn't open.
On this advice from Ardern, Cabinet agreed to move New Zealand to alert level 3 that day and agreed in principle to move to alert level 4 "at the earliest practicable opportunity and no later than within 48 hours, for an initial four-week period".