Less than a month ago, New Zealanders disappeared into their homes, retracting from the public domain like spilled water into a dry sponge. The motorways and city streets stood mostly empty, shops closed, schools and playgrounds were deserted. A single case of the highly contagious Delta variant had been detected and the government called a snap level-4 lockdown, introducing some of the strictest restrictions in the world.
It was a new threat for a country whose Covid-zero pandemic response had been ranked one of the best globally. New Zealand had never faced a Delta outbreak before, and no one knew if its past strategies would prove up to the task.
Across the Tasman, a bleak picture was emerging: Australia, like New Zealand, had maintained a zero-Covid elimination strategy throughout the first year of the pandemic but was now struggling with outbreaks in New South Wales and Victoria. Both countries had less than a third of their total populations immunised. With cases in NSW now regularly hitting more than 1,400 a day, the state provided a stark worst-case scenario of what New Zealand might see.
But now, against all odds, New Zealand is bending the Delta curve.
“It’s looking very good for ending this outbreak,” says Prof Michael Baker, an epidemiologist and public health expert. “I wouldn’t say ‘absolute certainty’, but it’s now far more a matter of when, rather than if.”
Left alone or managed half-heartedly, the Delta variant’s exponential growth quickly turns a trend line vertical. For many countries in the midst of outbreaks, the goal is to change that precipice to an incline – distributing the peak over a longer period so that health systems don’t collapse, resulting in needless deaths. In New Zealand, and for a few other Covid-zero Asia-Pacific states, the goal is more ambitious. They aimed to not only ease down the growth line, but to bend the curve completely, forcing case numbers back to zero and wiping out transmission completely. Today, just under a month from when the variant arrived in New Zealand, that goal suddenly looks within reach.
After peaking at the end of August at 83 cases a day, cases have been steadily tracking down – daily numbers haven’t passed 21 over the past week. Midweek, they dropped to 15, and then to 13, then 11. Modellers predict that – barring disaster – cases should hit single digits next week. Auckland, the centre of the outbreak, remains at alert level 4. But most of the country left a hard lockdown on Wednesday, flocking back to restaurants, cafes and schools.
It hasn’t been an easy path. In August, as the outbreak began, Baker told the Guardian it was an infectious disease expert’s nightmare. Nightclubs, churches, restaurants, hospitals, schools – the list of exposure events read like a checklist of every high-infection-risk gathering imaginable.
It also hasn’t been a path free of naysayers. Internationally, some parties portrayed the response at first as an overreaction – disproportionate to case numbers – and later, as case numbers climbed, as a hopeless, futile effort in the face of a variant that had overwhelmed others’ defences.
“Any state and territory that thinks that somehow they can protect themselves from Covid with the Delta strain forever, that’s just absurd,” the Australian prime minister, Scott Morrison, said. “New Zealand can’t do that. They were following an elimination strategy. They’re in lockdown.”
But New Zealand’s government has so far been unwavering in its commitment to elimination – a strategy that has allowed residents to maintain a life of relative normalcy for most of the past year. The prime minister, Jacinda Ardern, said: “While we know that Delta is a more dangerous enemy to combat, the same actions that overcame the virus last year can be applied to beat it again.”
Experts say the same essential toolkit is working.
“I think we can say, more or less, that our alert level 4 has got the measure of Delta,” says Prof Shaun Hendy, epidemic modeller for research centre Te Pūnaha Matatini.
“Early on, we were trying to think about how effective alert level 4 would be, and were thinking it could be substantially less effective against Delta over what we saw in the March, April outbreak,” he says. “But actually it’s been very similar – performance has been helped by the vaccination rates, no doubt. But basically it’s worked almost as well as it did last year. A couple of weeks on, it does look like we’re on track to eliminate the outbreak.”
Compared to previous outbreaks, “this has been an order of magnitude more severe and has really tested our systems”, Hendy says. “Our systems, you can never say that they’re good enough. But in this case, we’ve just lifted our game enough that we’ve brought this under control.”
The trajectory of the latest outbreak can also provide a certain amount of reassurance for New Zealand that the country’s “go hard and go early” strategy can contain a Delta outbreak.
New Zealand also has the opportunity to learn something from Australia’s experience.
At the moment, “I think it’s a cautionary tale for us”, says Dr Siouxsie Wiles, a microbiologist and one of New Zealand’s central pandemic communicators. “They show what happens if you don’t control transmission. And I guess what they have shown also is if the virus gets into essential workers and their workplace.”
Experts are careful to warn that there is still a long road ahead – as well as absolute numbers declining, New Zealand also needs to push up the percentage of cases without “exposure events”, or that are isolated for the duration of their infectious period. “If we see declining numbers but we also have several days seeing no unexpected cases, that’s very reassuring,” Baker says.
What happens next?
If New Zealand does successfully eliminate the Delta variant, it still raises questions of what next for a country that has used extremely strict border controls to remain Covid-free thus far. The government had released a tentative plan for reopening just days before the outbreak began. But on Wednesday, the Covid-19 response minister, Chris Hipkins, said that might need to be re-evaluated. “It would be fair to say that Delta has actually changed some of the thinking about that, even in the last few weeks,” he said. “Delta has changed the game.”
New Zealand’s elimination strategy means it has avoided most of the economic, social and public health toll of Covid so far. If New Zealand manages to wipe out Delta again in the coming weeks, that is an advantage it may seek to hang on to.
“We’re in the privileged position of just a few countries on Earth … that excluded the virus,” Baker says. “We can keep options open. We are choosing when to engage with the virus, whereas most of the world has no choice. I would be loathe for us to surrender that advantage we’ve got, until we’re ready to do it on our terms.”
“I’m very optimistic that we can get to elimination,” Wiles says. She pauses, then amends to: “I guess cautiously optimistic.
“We are in this position because of one case, and so we just have to be really mindful of that. One case could be all it takes.”