The government is making it mandatory for people to wear masks while they are visiting essential services, including supermarkets and petrol stations.
Prime Minister Jacinda Ardern and Director-General of Health Dr Ashley Bloomfield have spoken to media about the latest developments, after New Zealand entered a nationwide alert level 4 lockdown overnight following acase of Covid-19 being found in the community yesterday.
Ardern said Cabinet has now confirmed its decision about mask use made earlier this week.
"From 11.50pm tonight, it will be mandatory for everyone aged 12 and over to wear a mask when they are visiting any of the essential services that are currently open, including supermarkets, pharmacies and service stations."
Staff will also be required to wear a mask.
Mandatory mask use will now also include places like bus terminals and taxis.
"Simply put, at level 4 if you are in a place that is allowed to be open to provide services to people, or transport, you must wear a mask.
"Wearing a mask is an act of care to the people around you," she said.
University of Otago primary health care and general practice senior lecturer Lesley Gray said - in comments provided by the Science Media Centre - "Mandating masks when visiting essential services is a good move given all we know about the Delta variant of Covid-19 at this point.
"Delta is highly transmittable and we do not yet know where the first case currently contracted this Australian variant of Delta from. Wearing a mask protects our essential workers and reduces risk of transmission from this airborne virus."
University of Auckland aerosol chemist Dr Joel Rindelaub said expanding mask mandates from public transit to other indoor areas was a wise move, as indoor environments were high risk locations for Covid-19 transmission and super spreader events due to their decreased air ventilation.
"Thanks to the increased transmissibility of the Delta variant, the US Centre for Disease Control (CDC) recently renewed their mask use recommendations. Thus, it makes sense for New Zealand to use what other countries have learned to help shape protection strategies against the ever-changing coronavirus.
"The Delta variant is a new threat, and we need to take new action to help fight it."
The prime minister also confirmed the Covid-19 Delta virus at the centre of the outbreak in New Zealand originated in Australia.
She said genome sequencing overnight has confirmed the outbreak is Delta, and secondly, that it is linked to the NSW outbreak.
Ardern said only three positive cases have arrived into MIQ from Sydney since 1 July. One on 9 August on their day one test, and two on 14 August on their day three test.
These three cases are being genome sequenced right now, as part of the usual processes.
She said there had not been any NSW cases at Auckland Hospital, so they were still looking for the link. One of the most recent cases is a nurse at the hospital.
Ardern said everyone who came from NSW and Queensland was compliant with the travel restrictions.
She said despite that, the government was preparing to contact all cases who have arrived from Australia should they find the community case is not linked to the three positive cases from MIQ.
Two new cases brings total to seven so far
There are also three cases found in managed isolation, he said.
The other four cases found earlier today include a work colleague of the case found yesterday, who has three flatmates including a woman who works at Auckland City Hospital and has been working in recent days. She was fully vaccinated.
Bloomfield said the wife of the original case has returned a second negative test
As of 11am, Auckland regional public health has identified 16 close contacts, 14 of whom have been contacted and the others are being tracked down.
He said there has been no trouble with compliance from contacts.
Wastewater testing has been taken from Rosedale, North Shore, and more samples are being taken across Auckland.
Bloomfield said some modelling suggested between 50 and 100 more cases and it was very important people not move about.
Ardern said New Zealand only need to look at New South Wales to remind us why it was so important to follow the rules, "who today have reported 633 cases, 92 were active in the community while infectious".
"Do vaccines make a difference? The answer is yes, an enormous one. To put it bluntly if you've had the vaccine you are less likely to catch Covid-19 and much less likely to get sick or die," she says.
According to the CDC the risk of infection is reduced threefold, but in some cases people who have been vaccinated can still get the virus, and spread it.
Ardern said 55,688 doses of Covid-19 vaccine were given out yesterday, a new record. Vaccinations have been paused to ensure public safety during the transition to alert level 4.
She said plans are being activated for all DHBs to resume vaccinations under level 4 conditions, and in some cases they will resume this afternoon.
People who were not home when lockdown began are being asked to return to the place they will be until the end of lockdown as soon as possible.
Ardern said people who have flights booked they are no longer able to use should cancel them, to allow people who may need a spot on a flight to use it.
She said there have been many reports from airlines of no-shows.
Bloomfield said it was very important that people who need acute medical care should receive it.
He thanked nurses who called off their planned strikes yesterday after the news of the outbreak and lockdown.
Ardern said most people are doing the right thing, according to Police Commissioner Andrew Coster. People may be nervous about Delta, but "we can get on top of this, just like we have every other time, if we do it together".
Ardern said there was still a risk to the South Island.
"So long as we are yet to pinpoint the exact source of this case, I cannot hand on heart tell you that the South Island isn't implicated. And so I would rather have more information in order to assure ourselves of that before we treat the South Island any differently."
She said some people have already been identified from the locations of interest who may be in the South Island.