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.
Six new cases in MIQ today
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.
