Researchers have offered the Government some "Plan B" options – such as trying to delay a peak in Covid-19 cases until next year – if New Zealand's promising elimination strategy fails.

A team of Otago University researchers have provided modelling to the Ministry of Health which sets out what approaches the country could draw on to manage an epidemic.

While that research is soon to be released by officials, a similar paper by the same team, looking at a hypothetical European country of 10 million, explores the same options.

It showed that strong interventions, such as generally reducing peoples' contact with others, could potentially push the epidemic peak into the following year, when a vaccine could be available and hospitals were better set up.


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Applying different levels of control proved the potential difference between 22 per cent and 63 per cent of the population becoming sick; between 0.2 per cent and 0.6 per cent becoming hospitalised; and 0.07 per cent and 0.28 per cent dying.

The paper's lead author, public health professor Nick Wilson, said New Zealand may have spared itself having to choose between such drastic decisions, like enforcing long-lasting mass quarantine measures, by closing its borders and going into lockdown early.

"New Zealand has gone down the eradication pathway, which I think is great and appropriate for island nations," he said.

"If we eliminate this, we can potentially keep up good border control. Because we don't have land borders, we are in a pretty ideal situation. We probably got there in time, whereas Australia has probably missed the boat."

But it was still possible our move to contain Covid-19 could fail.

"This is what this particular paper is really looking at. We could go down the mitigation route of trying to 'flatten the curve', or we can really try to suppress it down and push the peak out to next year, when hopefully it won't matter as much because we'll have vaccine.

"It's also about buying time to allow treatments to be improved, and to make intensive care units in hospitals more efficient. We're seeing enormous efforts around the world on this."


In the event New Zealand was left in such a position, Wilson said a staggered approach of releasing controls on society might prevent a rapid "bounce-back" of cases.

"For New Zealand, it could mean a terrible trade-off between health and minimising deaths and getting the economy going again."

It might mean releasing restrictions on younger workers, while keeping older people isolated.

"But this is such unknown territory we're in, that we just don't know how people can cope with all of this home quarantine and restricted activity," Wilson said.

"New Zealand does have a good shot at this because there is trust in government – unlike in America – and we're a small, relatively cohesive society, with good social capital that the Government can make use of.

"But, right now, I think we're in a much better position than other countries, through a mixture of chance, and being lucky with the timings of the season as well.

"Winter is still a couple of months away, and by that time, hopefully we would have increased our coverage of the flu vaccine and learned a lot of lessons from Europe and North America about how to expand our ICU capacity."

The paper was published before modelling by another group of researchers, from Te Punaha Matatini, showed that - failing eradication - lockdown measures like those in place could delay a peak for up to 400 days but wouldn't prevent it.

Any relaxing of those measures could result in hospitals being overwhelmed with a surge six times that of hospital capacity within a few months. The Government's official Covid-19 advisory website