Twenty-five close contacts of the quarantine worker at the centre of New Zealand's latest Covid-19 outbreak have been put into isolation.

The Auckland Jet Park worker has tested positive for Covid-19, the Ministry of Health has confirmed. At this stage there has been no further spread - that case is the only new one reported today.

"We have identified 25 close contacts of the worker, and they have all been contacted, are isolated, and are being tested." the ministry said. "To date, six have returned a negative test result and the remaining are pending.

"As in other cases, this person quickly got tested after developing symptoms, which has allowed us to act quickly to stop the spread of the virus."

The ministry also revealed it has uncovered a historical case - someone who arrived n New Zealand on October 5 from London via Singapore.

Upon arrival at their managed isolation facility they alerted staff to their previous positive test which was confirmed in London on September 19.

They were tested again and returned a positive result on October 5. The mnistry said it was likely an old infection, consistent with the earlier positive result.

"We are awaiting confirmation that the case has been recorded in the United Kingdom totals, and until then are classifying it as a historical case which will be reported in our case numbers."

The ministry says because the person works at the facility and is not a returnee they are considered a community case.

The person has been tested regularly as part of the routine testing for staff in the facility, most recently being swabbed on November 3 and returning a negative test on November 4.

People who were at Auckland’s Mezze Bar between 11:00 am and 1:00pm on Thursday 5 November are being asked to watch for symptoms after the case visited the bar before being diagnosed with COVID-19.​⁣

— Unite against COVID-19 (@covid19nz) November 6, 2020

The staff member developed symptoms yesterday and was tested again. That test had returned a positive result, the ministry said.

People in contact with the worker are being traced, isolated and tested.

Two businesses in Auckland have been contacted by Auckland Regional Public Health Service and notified that the worker visited their premises during their infectious period.

A push notification has been sent via the NZ Covid Tracer to everyone who scanned in to these businesses around the relevant time.

The ministry said in a statement that managed isolation workers were regularly tested.

As in other recent cases, this worker quickly got tested as soon as they became aware of symptoms. The early identification of cases along with rapid contact tracing assists in stopping any spread of the virus.

Auckland's Mezze Bar and a Queen St bottle shop were the two businesses where the man had been when he was infected.

Anyone at the Mezze Bar between 11am and 1pm on Thursday is considered a casual contact. They should watch for symptoms, and get tested if they feel unwell, ARPHS said.

A spokesperson from ARPHS said the person dined alone, and no close contacts had been identified at the restaurant.

The case also went to a bottle shop Liquor.Com on Queen St on Thursday for 15 minutes around 1.30pm.

Any people who visited around this time between 1pm and 2pm were also casual contacts and should watch for symptoms, the spokesperson said.

"The case's close contacts at home and at work have been identified and are all self-isolating and are in the process of getting tested."

Mezze Bar owner Sally Hindmarsh said she was contacted by health officials just before 7pm with the news.

"First of all I actually thought it was a crank call so I rang them back and got them to email me."

Once she realised it wasn't a prank, her reaction was one of dismay.

Hindmarsh said there were people at about six tables so she immediately told them there had been a person at the bar the day before who had since tested positive. She then closed the tapas bar and would spend the rest of the evening carrying out a deep clean.

"We are being very, very vigilant with our cleaning process and it's all going to be good to go tomorrow."

She said it wasn't very busy during the time the person visited yesterday and the advice to anyone who was there, including six staff members, was to get tested if they were worried or started to show any symptoms.

The ARPHS spokeswoman said people who scanned the NZ Covid-19 Tracer app at the Mezze Bar or Liquor.Com during these times should receive a notification, confirming they were there around the same time as the case.

Patrons and staff should look out for symptoms of the virus over the next 14 days. If they develop symptoms, they should ring Healthline on 0800 358 5453 or their GP and be tested.

The symptoms of Covid-19 are a new or worsening cough, sore throat, runny nose, loss of sense or smell, or fever.

This is the seventh time - and probably the eighth time - in just over three months where Covid-19 has been passed from inside a managed isolation or quarantine (MIQ) facility into the community.

The others are the Rydges maintenance worker, the Jet Park nurse, the overseas returnee who caught Covid from a shared rubbish bin lid and tested positive after leaving MIQ, the port engineer, and the two Sudima nurses. The August cluster is also likely to have come from an MIQ facility, though there is no evidence.

The infection prevention and control measures have been audited twice and are currently being looked at by Associate Health Minister Ayesha Verrall, who is an infectious diseases specialist, in light of recent cases among border-facing workers.