Health officials are investigating a suspected case of Covid transmission inside an Auckland managed isolation facility.
The case involves guests at the Grand Mercure isolation hotel in relation to a day 12 case at the facility.
Results from genome sequencing show a link between two guests at the Grand Mercure.
The returnees were staying in separate rooms on different floors. They arrived on separate flights within two days of each other. An investigation into the source of the infection is under way, the Ministry of Health said.
At this stage, no other cases within the facility have been found linked to these two cases but investigations continue.
As a precautionary measure, about 250 returnees who have left the facility since March 10 are being contacted today, asked to get tested immediately and remain in isolation at home until a negative result is returned.
Additional on-site testing is also being provided and exit tests put in place for all returnees leaving the facility.
One of those cases is the Covid-positive person who took two bus journeys from the hotel to an exercise area, leading to the rest of those on the bus to be required to start their two weeks of isolation again.
The classification of the 14 returnees who were also on the bus as close contacts was based on a public health assessment of the exposure event on the vehicle.
The assessment would have included consideration of proximity to the case, amount of time that they may have been exposed, how infectious the case was likely to have been at the time, whether the virus was a new more infectious variant, and whether infection, prevention and control protocols were followed.
The virus in this case was the more infectious UK variant of Covid-19.
The Ministry of Health reassured the public there was no evidence of any Covid-19 cases in the community connected to this situation at this time.
The Ministry of Business, Innovation and Employment (MBIE) was conducting an internal investigation into the bus journeys to determine what happened and what improvements, if any, could be made to strengthen their processes.
There are six new Covid cases reported today, all in managed isolation.
The cases are travellers from Denmark, India and Serbia and Montenegro.
Meanwhile health officials said the household of the infected MIQ worker remains under investigation.
One relative returned a "weak positive" result after their first test and as a precaution, some colleagues at Countdown Quay St who worked closely with the person under investigation will stay home until they receive a day 5 negative test.
Shoppers and other staff are not considered to be at risk.
The Ministry of Health said testing across Auckland remained steady. On Wednesday 6209 tests were processed bringing the seven-day rolling average to 4575.
The total number of tests processed by laboratories to date is 1,867,966.
An update to the NZ Covid Tracer app now means another 100,000 New Zealanders with older iPhones will be able to turn on the Bluetooth tracing function of the app.
Version 4.0.0 has now been released to extend Bluetooth support to iPhone 5S, 6 and 6+.
Today's case numbers come as the Government yesterday assured people there was little risk to the community after news of a Covid-positive MIQ worker.
Genome sequencing has linked the MIQ cleaner's case to a returnee who was staying at the same facility - the Grand Millenium.
One of the worker's household members returned a weak positive test but a second test came back negative.
The Ministry of Health said that could indicate an early and fleeting mild infection that has now passed, or it could be a false positive. The household contact will remain "under investigation" and be managed as a close contact.
The rest of the household tested negative and the only location of interest listed by the Ministry of Health was the Countdown supermarket in Mt Roskill. Shoppers at the store between 3pm and 3.15pm on March 20 were classed as casual contacts and were asked to monitor their health until April 3 and get tested if they became unwell before then.
It was yesterday revealed the worker also visited Best Start childcare in St Lukes on Friday to collect a grandchild. It was closed for deep cleaning on Tuesday and parents had been informed.
A Ministry of Health spokesperson said the visit to the childcare centre was a "very low risk" of infection because the case spent less than 10 minutes picking up the child, without being in close contact with anyone.
Countdown Quay St also closed for deep cleaning on Tuesday after a staff member returned a weak positive result.
There were no new community cases reported yesterday however there were three in managed isolation.
Covid-19 Response Minister Chris Hipkins also outlined the criteria for early vaccination yesterday.
Top athletes and Kiwis visiting a dying loved one overseas would be among those eligible to jump the vaccine queue and get their jab early, he said.
To receive early vaccination under the national significance criteria an applicant must be representing New Zealand in an official capacity, at significant international events, or in an official non-government capacity.
Compassionate grounds would only be considered for those who needed to provide critical care or protection for a dependant, those who needed to access critical medical care not available in New Zealand, or anyone visiting an immediate family member who was dying.
These exemptions did not, however, apply to those looking to go overseas to attend a funeral.
New Zealand's general vaccine rollout will begin midway through this year but the new criteria meant certain people could get the vaccine early.
Only those who needed to travel before August 31, who had already made commitments to return to New Zealand after they travel, would be eligible.
Hipkins said New Zealand's Olympians were expected to be eligible. The Black Caps were also likely to get early vaccination so they could compete in the ICC World Test Championship final in the UK in June.
But those who are given the green light to get the jab to go overseas will still have to stay in managed isolation in New Zealand when they return home.
Hipkins also said the Government was "broadly on schedule" with vaccinations but when pressed, director general of health Dr Ashley Bloomfield conceded that the rollout was "slightly behind schedule".
"We have delivered about 93 per cent of where we plan to be so far," Bloomfield said.
Hipkins said 41,500 vaccines had been administered – that's up roughly 14,000 on the week prior.