One of the new cases of Covid-19 visited an aged-care facility in the Waikato.

Director general of health Ashley Bloomfield made the announcement today during an update on the country's new cases of Covid-19.

It comes after the re-emergence of community transmission in Auckland on Tuesday.

Bloomfield said there were 13 new community cases today, all linked to the original four confirmed cases from the new outbreak in South Auckland.

The new cases include children. One is a girl aged 1 to 4 while the other is a boy between the ages of 5 and 9. Another girl who tested positive is aged between 10 and 14, while a teenage male (age from 15-19) is among the new cases.

Among those were three cases at Auckland coolstore Americold linked to the outbreak, revealed this morning by the Herald. Another seven were family members of these employees.

Bloomfield also revealed one of the new cases had visited an aged-care facility in the Waikato over the weekend.

Bloomfield said he wouldn't the name facility yet as family members were still being notified.

The visit was when the person wasn't displaying symptoms but they developed symptoms the next day.

The visit was to a family member resident and the visitor saw their family member and was in contact with several staff.

All staff and residents in the unit will be tested.

Bloomfield thanked the facility for their response.

It comes after Aged Care Association chief executive Simon Wallace said yesterday all New Zealand rest homes had moved to alert level 4, meaning strict lockdowns and barring family visitors.

"Rest homes are on level 4 lockdown for at least three days. Full lockdown means effectively we are operating at level 4. It means there will be no family visits to their loved ones in a rest home," Wallace said.

"We've seen what's happening in Melbourne where aged care has been affected. More than 100 rest homes in Melbourne have had Covid-19 outbreaks and they didn't move quickly enough. We can't afford to take any risks at all."

Bloomfield said although all aged residential-care facilities were closed to the public, anyone who has visited the facility recently should also closely monitor their health and seek advice if they had any concerns.

Waikato DHB have confirmed they are today testing all staff and residents.

The facility has isolated the area visited from the remainder of the facility.

The DHB has staff on standby in the event that they're needed if the staff need to be stood down.

The DHB has ensured that the facility has all the PPE it needs.

Six rest homes had Covid-19 cases during the previous outbreak, two of which - Rosewood Rest Home in Christchurch and CHT St Margaret's in Auckland's Te Atatu - accounted for 16 of the country's 22 Covid-linked deaths.

An independent review found delays in realising Covid-19 was spreading within some rest homes meant more people were infected.

Bloomfield also confirmed today a Mt Albert Grammar student in Auckland tested positive - a person who was a close contact of the family whose members have tested positive.

He did not know if the student was one of the four probable cases announced yesterday.

He said some of the original family who had tested positive were in a quarantine facility but not all of them.

Bloomfield revealed further details about the family's trip to Rotorua and Taupō over the weekend, and urged anyone who was in these places at the same time to get tested.

On Saturday the family checked in at 3.30pm to the Wai Ora Hotel in Rotorua.

They visited the Herbs and Spice Thai Restaurant at 8pm that evening.

The following day at 2.30pm they visited the Pak n Save supermarket at Amohau St in Rotorua, before heading to Heritage Farm and 3D Art Gallery at 3.30pm.

At 4pm they then headed to the Skyline Gondola and Luge.

The following morning on the 10th they visited Sail Barbary Eco Sailing in Taupō at 10.30am before returning to the Heritage Farm and 3D Art Gallery at 3pm.

There was also a visit that evening at 7pm to Burger Fuel Redwood Centre in Rotorua. On their way home, the family stopped for fuel in Hamilton at 9am on Tuesday morning.

Cabinet ministers will meet tomorrow to decide whether Auckland might be eased into alert level 2, stay at level 3, or moved to full lockdown.

Tomorrow's Cabinet decision on the future of the lockdown will depend on factors including the extent of the new Covid-19 outbreak, the containment of known chains of transmission, and whether the source of infection has been found.

Bloomfield would not say this morning how he thought the decision would go.

"We are getting all our information together so we can get the best possible advice. I feel confident we will have a lot more good information to inform a good decision," he told Newstalk ZB's Mike Hosking.

Meanwhile, the Lakes District Health Board has released further information about where two people who tested positive for Covid-19 visited while in Rotorua, including the Fat Dog cafe on Sunday, August 9 between 1.30pm and 2.30pm and Burger Fuel Redwoods on August 10 between 7pm and 8pm.