Level 4 saves 80,000 lives

New research suggests up to 80,000 Kiwis could die from coronavirus without strict measures such as the countrywide lockdown.

It also shows that the lockdown may have to last far longer than a month to keep the strain on the healthcare system manageable.

But one of the paper’s authors said New Zealand’s speed at adopting a lockdown could mean we ‘‘stamp out’’ the disease much faster.

The modelling from the University of Auckland’s Te Punaha Matatini data research centre was provided to the Government before it made its lockdown decision, and builds on research overseas that has informed governments around the world in instituting dramatic lockdowns. On Sunday, initial modelling suggested as many as 60,000 Kiwis could die if stringent measures weren’t implemented.

It finds that within 400 days roughly 89 per cent of the population would get infected, far exceeding the capability of our hospitals to cope and causing up to 80,000 deaths. New Zealand hospitals could deal with about 40,000 cases.

Only population-wide social distancing with a lockdown and the closure of almost all businesses and schools could keep the case numbers down enough for the healthcare system to cope, with a mortality rate of just 0.0004 per cent: About 20 people.

However the cases would spike the moment these measures were lifted, unless a vaccine had been developed.

This suggests massive restrictions could be in place for a lot longer than four weeks.

However the Government could reduce restrictions when the infection rate was low and then rapidly clamp them back on when the healthcare system approached capacity. This would be useful to gradually develop ‘‘herd immunity’’.

This could involve cycling between level 4 and 3, possibly with different regions of the country being in different levels at the same time.

But the researchers caution that this kind of huge social control over daily life has yet to be fully tested in a comparable country. They also note that building up this herd immunity could take up to 21⁄2 years.

One of the paper’s authors, Shaun Hendy, told Stuff it was possible that New Zealand’s actions could see the disease stamped out relatively quickly.

‘‘The fact that we’ve gone early and we’ve gone for that suppression strategy means we have bought some time for those contact tracers and testers to stamp it out,’’ Hendy said.

‘‘We are possibly unique amongst our normal comparative countries.’’

Hendy said New Zealand had a ‘‘bit of luck’’ as the disease had reached our shores relatively late, and there was still not a huge amount of confirmed community transmission.

He said it was key that people obeyed the lockdown instructions – particularly in large urban areas.