Coronavirus: Christchurch not facing lockdown after new community case - Jacinda Ardern

Prime Minister Jacinda Ardern has confirmed Christchurch isn't facing an imminent alert level move after a community COVID-19 case was detected in the Garden City on Monday.

On Monday night, the Ministry of Health released a statement saying a staff member at a Christchurch managed isolation facility had contracted COVID-19. While they had tested negative during routine testing on Thursday, they became unwell over the weekend and sought out another test, which came back positive.

While the individual is now in isolation, they did visit a Countdown supermarket on Colombo St in the Christchurch suburb of Sydenham on Sunday. That store has now been deep-cleaned and will reopen on Tuesday.

The Prime Minister told The AM Show on Tuesday morning that Christchurch residents shouldn't be concerned the city is about to face a lockdown.

"Definitely not facing anything like that. This actually is an example of exactly what we've built all of our systems and expectations around," she said.

New Zealand's alert level system doesn't require the country to move into lockdown just because a single community case has been found.

Aotearoa is currently at alert level 1. That's when COVID-19 is "uncontrolled overseas", there are "sporadic imported cases" and "isolated local transmission could be occurring in New Zealand".

Alert level 2 comes into play when there is "limited community transmission" occurring and "active clusters in more than one region", while a lockdown may happen when there are "multiple cases of community transmission" or a widespread outbreak.

The last time part of New Zealand went into lockdown was when four community cases were found in Auckland in August. Those cases appeared very suddenly and without a clear source of transmission. Months on, it is still unknown exactly how the outbreak began.

Ardern said on Tuesday morning that the infected Christchurch individual's one household contact has tested negative while their workplace contacts are in the process of being tested. That's on top of the usual routine testing that border workers are subject to.

"This is exactly what the system is built for. We expect from time to time, because of the nature of this virus, that this may happen. You recall we have had this happen before and it's always been very tightly managed without needing to move levels."

Ardern said the case is a reminder to Kiwis to continue using the COVID Tracer App.

"Make sure wherever you go, you are scanning in. It makes the job of notifying you much, much easier for us."

That is echoed by epidemiologist Dr Michael Baker, a professor of public health at the University of Otago. He told Newshub on Monday night that there is always a risk of transmission between people in managed isolation and border workers.

He wants Kiwis in Christchurch to be alert to any symptoms and stay home if they become unwell.