Coronavirus: New Zealand needs more time before moving to alert level 1 - Michael Baker

New Zealand appears to be winning the battle against SARS-CoV-2, the strain of coronavirus responsible for COVID-19. The country has settled into life under level 2 with a degree of confidence - a "gold standard" of contact tracing, watertight borders and no recent cases of community transmission. However, one key factor is missing. 

Public health expert and Otago University professor Michael Baker says time is of the essence - and there simply hasn't been enough of it to warrant risking a move into alert level 1.

When asked by The AM Show host Ryan Bridge what is stopping New Zealand from moving into level 1 - a mere rung on the ladder away from normality - Baker said "time" is the crucial missing link.

"We know you can have chains of transmission that go on for many weeks - we've seen this in China, where they have still seen cases a month after coming out of lockdown. That's the concern. I think this is being very cautious, but I think that's what most New Zealanders want," he explained.

"You can show with modelling that if you have four weeks with no cases, you've got more than a 95 percent chance that the disease has gone. That doesn't mean that some of the cases now wouldn't necessarily all count - because they may have occurred several weeks ago in terms of when they got infected."

Baker agreed a lack of trust is also playing a part in the hesitation to move into level 1, as it's "human nature" for some New Zealanders to flout the current level 2 restrictions - actions which may impact the progress the country has made in flattening its curve. 

"This is a new disease. We're all learning... we haven't lived through a pandemic before. Societies that are more used to this will be doing a lot more than New Zealand - they will be wearing masks on their public transport, which I think is still a missing element in New Zealand. It's actually interfering with public transport getting going again," he said.

"Somewhere like Taiwan... they haven't had any transmission for over a month, but they just passed a law there requiring masks on buses and trains."

The effectiveness of masks has become a hotly debated topic across the world, with New Zealand's Director-General of Health Dr Ashley Bloomfield noting there is not enough evidence to warrant the mandated use of masks in public settings. However, findings of a recent Hong Kong-based study found masks did provide protection against the virus - a stance many countries have taken in their bids to flatten the curve. 

Dr Bloomfield has previously stated that masks can do more harm than good if they are ill-fitting and require frequent re-adjustment, meaning bacteria on the hands is constantly in close proximity to the mouth and nose. 

Under level 2, public transport has resumed its normal operations. Despite there being strict physical distancing measures on-board, masks are not required to be worn on buses and trains in New Zealand.

Increasing cap on social gatherings should be reserved for level 1

Baker implied that the potential extension of the cap on social gatherings should be reserved for level 1. The current restriction, which requires all gatherings in social settings - whether it be in the home or in public spaces - to be limited to a maximum of 10 people, will be reviewed by Cabinet on Monday afternoon.

"We still have the virus potentially in New Zealand and the real time to celebrate is when we get down to level 1. Level 2 is really about holding back on the events that we know are related to [the] transmission of this virus - essentially big social gatherings where this is alcohol present," Baker said.

"I think a nuanced approach here would be useful, but we still have to remember why we're doing this. We've only recently just relaxed the rules about having a lot more socialising, and we know this is how the virus gets transmitted. It would take one to two weeks to see the effects of that - so we really want to be very cautious."

The rule has proved controversial among New Zealanders, as the cap formerly applied to events including funerals and religious services. It was announced last week that Cabinet will be reviewing level 2 restrictions on a fortnightly basis.

Elimination vs eradication

Baker also clarified the difference between elimination and eradication, the former - the goal of the Government's response - characterised by Dr Bloomfield as "keep-it-out, stamp-it-out".

Despite days of no new cases, Baker says New Zealand has not yet "eradicated" the virus and this should not be used as a reason to question the alert level 2 restrictions.

"Eradication is a global absence of a disease and unfortunately that's not the case here. Elimination is when you reach an agreed threshold. Some of the cases we're getting you wouldn't necessarily count, you have to look at each one on its merit - in terms of whether it's part of those 28 days or should be put back to an earlier date," he explained.

Local epidemiologists have discussed the elimination threshold as being 28 days of no new cases, based on the date of onset of the most recent case.