Coronavirus Covid-19: Why the Auckland community case could trigger a swift move to lockdown

Last week Covid-19 Response Minister Chris Hipkins told us to expect an alert level 4 lockdown if any Delta cases pop up in the community.

Now we have a community case in Auckland with no link to the border yet, which has triggered an emergency meeting of senior ministers.

If it is a case of the Delta variant, a strict lockdown would be needed because we know complacency has once again struck our QR scanning habits, our contact-tracing systems can't stay ahead of a Delta outbreak, and the Auckland population is still mostly unvaccinated.

Auckland hospitals also can't afford to be overrun.

It's unknown yet if surge vaccination might be an option in Auckland to try and dampen any spread. It wasn't an option during the Delta-scare in Wellington in June because we didn't have enough vaccine supply or enough workers.

Even if it's unclear what strain it is and we have to await genomic sequencing results, the Government could be justified in imposing a level 3 or 4 lockdown on the chance that it might be Delta.

That didn't used to be the case. Pre-Delta days saw the Government take 72 hours to find more information with a minimal escalation in alert levels.

But in prepping the country for a level 4 response to Delta, Hipkins pointed to the ongoing outbreak in New South Wales, which continues to balloon despite weeks of increasingly stringent lockdown measures.

It was sparked by a single limousine driver transporting aircrew, and today there were 452 new local cases, with the source of 323 of those cases still under investigation. The death toll is now 57, and three in four cases there are people under 40.

Last week's release of the letters from the expert panel chaired by Sir David Skegg revealed that "New Zealand is liable to experience an outbreak similar to that in New South Wales over the coming months – although presumably we would go into lockdown more quickly".

Delta has a shorter incubation period, sends more people to hospital, is more infectious for younger people and is considered at least twice as transmissible as the original virus.

As if anyone needed a sobering reminder, this morning the Ministry of Health revealed how it had spread from one room to another in the Jet Park quarantine facility via two doors that were open for a few seconds at the same time.

Its R0 value is considered as high as nine - meaning one person on average infects nine others.

If we're dealing with Delta in the community and the person has had a particularly busy social calendar in the previous days, which may have also included countrywide travel, it's easy to see how it might have already spread to dozens of people.

It's also possible that the person is one of those Covid-duds who don't spread the virus.

But Prime Minister Jacinda Ardern's success in keeping the virus at bay has been based on a cautious approach so far, so expect the same from her when she provides an update later this evening.