The Government is moving Auckland into level 3 lockdown after four cases of Covid-19 emerged with no known connection to overseas travel.

Here is everything currently publicly known about those cases.

The “index case” – the first case the Government found out about – is a man in his 50s who lives in south Auckland, the Ministry of Health said.

He was swabbed on Monday after displaying symptoms for five days, including a fever and a cough. He was tested again to confirm the positive result.

The person had no overseas travel history or immediate link to someone who did, or a high-risk worker such as someone who worked at a managed isolation hotel or at the border.

"There is no immediate link we have found as yet to a managed isolation facility, and there is no connection to a high risk person, such as those who work at the border,” Ardern said.

“Community transmission” is the name given to new cases with no clear origin for the infection – such as overseas travel or a close connection with someone who had travelled overseas recently.

Their close contacts were then tested, including six family-members. Of those, three were found to also be positive – including a preschool-age child who does not attend an Early Childhood Education facility.

Mt Albert Primary School in central Auckland has been closed as someone who lives in the affected home is a pupil at the school.

In a letter from Auckland Regional Public Health Service (ARPHS) dated August 11, the school’s community was informed of the positive tests.

“A child at Mt Albert Primary School lives in a household where a number of people have been confirmed with Covid-19,” the letter reads.

The letter said the school would close on Wednesday morning for 72 hours so ARPHS can complete an investigation.

After the investigation is done, the school will reopen and operate under Alert Level 3 guidelines, unless advice is for it to remain closed.

Two of the cases have gone to work recently at workplaces in the wider Auckland area, meaning a city-wide lockdown was needed, Prime Minister Jacinda Ardern said.

Those workplaces were not “customer-facing” and the Ministry of Health is currently working with them directly. Ardern did not reveal the exact location of the businesses, saying they were small enough that this could identify the people involved.

The cases are currently self-isolating at home as are all their close contacts.

Interviews with public health units had been completed on Tuesday night and health staff were still with the family.

Ardern said the Government was considering whether the family should move to a quarantine facility.

Bloomfield said he was confident that Covid-19 had not been lingering around South Auckland since the last-known community transmission 102 days ago.

“If you reflect back to that period of time when we were coming down from level 3 and 2 we did extensive testing right across the country, including a broad ethnicity spread as well. So yes I think we can be confident – the fact that we went over 100 days, and the number of tests that we did, and the geographic and ethnic spread of those tests, we can be very confident,” Bloomfield said.

However he was expecting to see other cases as the contact tracing and testing took place, as the origin was still not clear.

“We’re expecting to see other cases,” Bloomfield said.

Ardern said if there are undetected cases in the community one would have elevated into the hospital system, and the Government had not seen that.