Early in the COVID-19 outbreak, the Government abandoned its existing pandemic strategy and gunned for complete elimination of the virus from our shores.
While a chorus of complaints came from business, politicians, conspiracy theorists and even some epidemiologists, it was the right call in virtually all respects, according to a new paper published in the British Medical Journal this week.
And it might change the way the world fights pandemics in the future.
"Elimination may now provide the preferred approach to managing emerging pandemics, which is a major revolution in thinking in this area," said University of Otago infectious disease expert Michael Baker.
Dr Baker and colleague Nick Wilson, along with University of Melbourne epidemiologist Tony Blakely said New Zealand, China, Australia and Taiwan have rewritten the rules.
"The typical approach of high income nations (such as those in North America and Europe) has been a 'suppression strategy', sometimes after initial use of a 'mitigation strategy'," their paper reads.
Suppression is when officials try to slow the spread of the virus - think 'flattening the curve' - but don't realistically think the virus can be eliminated. The advantage of this approach is the health system doesn't get overwhelmed, and life carries on otherwise as close to normal as possible.
"These approaches are largely consistent with plans designed to mitigate or suppress pandemic influenza."
Change of plan
That was New Zealand's plan too, but in mid-March it became clear to Prime Minister Jacinda Ardern we didn't have a health system that could cope with the carnage COVID-19 was wreaking overseas.
"I remember my Chief Science Adviser bringing me a graph that showed me what flattening the curve would look like for New Zealand and where our hospital and health capacity was," she told the Associated Press last week. "The curve wasn't sitting under that line. So we knew that flattening the curve wasn't sufficient for us."
As a virus new to science, almost every human alive was susceptible to SARS-CoV-2. Asian nations, having been through the SARS crisis in the early 2000s, immediately went to extreme lengths to rid themselves of the virus, or keep it out altogether. With the notable exception of New Zealand - and later Australia - Western nations didn't. Hundreds of thousands have died in Europe and North America as a result, while New Zealand's death toll is just 25.
Dr Baker hopes this new paper will encourage officials in other countries to go hard, even if they can no longer go early.
"Over the course of this year, we have been in regular contact with overseas colleagues, particularly in the UK, who are advocating for their governments to take an elimination or 'zero covid' approach. The emergence of an apparently more infectious virus variant is just another reason to eliminate this infection."
Pandemics and infectious diseases typically hit disadvantaged minority communities hard. Dr Baker and Dr Wilson say by stopping the outbreak altogether, "serious health inequities" were avoided that would have happened even under a suppression strategy.
Economic results
Much of the opposition to New Zealand's strict lockdown - which under level 4 back in March and April, was the strictest in the world - was economic. Business leaders feared a loss in profits, while workers feared losing their jobs altogether.
While New Zealand's GDP did take a sharper turn down than most, it's bounced back better too - and unemployment never got close to the dire predictions of double-digit joblessness.
"Countries following an elimination strategy - notably China, Taiwan, Australia and New Zealand - have suffered less economically than countries with suppression goals," said Dr Wilson.
"Our analysis was based on gross domestic product (GDP) projections for all of 2020 from the International Monetary Fund."
Tourism, for example, has been hit everywhere - regardless of border restrictions.
"Iceland reopened to tourism, but the demand remained low, imported cases of COVID-19 increased and the net effect was a larger decline in GDP than was seen in New Zealand," said Dr Wilson.
In recent weeks, many countries which failed to adopt an elimination strategy have found themselves enacting tougher and tougher restrictions. Sweden, which early in the pandemic was held up as a model for how to deal with COVID-19 without lockdowns, is now looking at new laws to restrict movement and close shops - but only after 8000 people died, and its economy went into a deep recession anyway.