The arrival of Omicron has "thrown a spanner in the works" for New Zealand's Covid response with a leading epidemiologist warning Kiwis to expect a "messy" 2022.
And director general of health Dr Ashley Bloomfield said it could lead to a reduction in the recommended time double-jabbed New Zealanders should wait before getting a booster shot.
New Zealand's first confirmed case of Omicron was announced yesterday, located at the Sudima Christchurch Airport MIQ facility.
Bloomfield told Newstalk ZB there have been no further detections of Omicron in those who travelled alongside the infected person on flights to and in New Zealand.
He said all the people on the flight that brought the people to New Zealand and the linking domestic flight to Christchurch were in quarantine and undergoing testing regimes.
"We'll be watching closely to see if there are any other positive tests," said Bloomfield.
While he couldn't rule out any further infections from the flight, he was certain this would not be the only case officials would encounter at the border.
"This will be the first of many Omicron cases we will see at the border," said Bloomfield.
"We are expecting most of our cases within a short period of time will be Omicron coming across the border and then we will deal with them and keep them at the border."
But he was very confident that Omicron would remain there, and not escape into the community.
Talking on TVNZ's Breakfast show, Bloomfield said the booster programme was a tool that will help keep the new Covid variant at bay.
Bloomfield said evidence from cases overseas showed the third booster jab was important in the fight against Omicron.
Bloomfield revealed that he had been given advice in the last couple of days on the time period between getting the second jab and the booster shot.
Currently, there is a six-month period between those two jabs.
He said the advice he has been given in recent days will be up for discussion among Government officials and ministers.
"It may be that a shorter interval will ensure that people do get that booster and increase to their protection at the right time in case we get Omicron in the country."
He expected there would be an announcement on bringing the booster shots forward before Christmas, but that was up to ministers to decide.
On opening up the border to Australian-based Kiwis mid next month, Bloomfield acknowledged that that is up for review now.
Cause for concern but not cause for panic - Robertson
Deputy Prime Minister Grant Robertson said this morning said he was not unnerved by Omicron on our doorstep.
"Obviously it's a cause for concern but it's not a cause for panic," he told Newstalk ZB's Mike Yardley.
He said the managed isolation and quarantine system had been set up to deal with a very highly transmissible variant and while it was not 100 per cent perfect it had served us well.
"We've set a framework up to deal with Delta we'll continually look at that and make sure it's appropriate to deal with Omicron.
"I've got confidence in our systems and we're working closely with the Ministry of Health and what we might need to do to tweak anything to do to be appropriate for Omicron."
He said while the new Covid protection framework did not have provision for the large national lockdowns we had previously used to quell outbreaks it did allow for bespoke lockdowns at a localised community level if needed.
Robertson said the Cabinet would meet on Monday to discuss the Omicron situation and added ministers continually met officials.
The booster situation to counter Omicron would be an important topic of conversation in coming days.
"The advice coming to the Ministry of Health is landing and we'll get advice in the next couple of days," he said.
Asked if the planned January border changes with Australia were in grave jeopardy, Robertson said the government would take another look at that with the latest information at hand.
He said while there were no plans to bring the decision forward it was important to use the most up-to-date information as the situation across the ditch unfolded.
"The Prime Minister has indicated we'll have another look in early January," he said.
On GDP, Robertson said the latest economic data showed resilience in New Zealand business.
"What it does show is the resilience of New Zealanders through Covid. We learnt a lot through the 2020 outbreak and so people realise we will bounce back and they don't need to panic."
'We were expecting it'
Bloomfield said: "We shouldn't be worried about Omicron at this point because we've caught it at the border.
"We found it in a managed isolation facility - we were expecting it," he said.
The measures we have at the border and the fact New Zealand reached 90 per cent full vaccination meant the country was as prepared as it could be right now.
Asked about lockdowns, Bloomfield said although that was not something any of us wanted to go through again - particularly Aucklanders - taking it off the table was not a smart thing to do during a pandemic.
He said if necessary - and if the health system became pressured - local lockdowns may still happen.
"What we've learnt over the last nearly two years of this pandemic is you use everything you've got when you need to."
Asked what he would be getting a break and what he has planned for Christmas, Bloomfield said he would doing everything he can to spend time with family and friends and enjoying a Kiwi summer - "if this jolly rain stops."
"This virus is quite clearly not done with us yet. But we've done incredibly well this year."
Bloomfield said hitting the 90 per cent full vaccination milestone was definitely something worth celebrating this Christmas.
Omicron's arrival - what we know
The news Omicron had reached New Zealand came on the same day the country reached 90 per cent of the population fully jabbed, and Covid vaccines for kids aged 5–11 were given the green light by MedSafe.
The confirmed Omicron case flew into New Zealand from Germany via Dubai on December 10. They are double vaccinated with the Pfizer vaccine.
The positive result was recorded on day two, and they are now staying in a quarantine wing in a broader MIQ hotel.
Bloomfield said the Air New Zealand flight crew and the driver who took the person to their hotel would be tested, and everyone on the flight was considered a close contact.
The case would spend 14 days in MIQ and Bloomfield said that health officials would now assume all border cases were of the Omicron variant until sequencing proved otherwise.
'2022 will be messy' - What Omicron's arrival means for NZ
Auckland University epidemiologist Rod Jackson said Omicron was always going to arrive in New Zealand, but the goal now was to keep it out of the community for as long as possible.
He said boosters may need to be brought forward, and international travel plans pushed back.
"Omicron demonstrates that nothing is for certain … 2022 is going to be messy."
"It's going to be uncertain, and Omicron has just thrown a spanner in the works. We just don't know how bad it's going to be.
"In terms of opening the border in January, I don't know. But I wouldn't be booking flights in January or February."
Last month the Government announced it planned to open the border to fully vaccinated Kiwis travelling from Australia in January – scrapping the requirement to stay in MIQ. Fully vaccinated Kiwis would be allowed to return from elsewhere in the world the following month.
Prime Minister Jacinda Ardern has indicated they plan to review this in the new year.
Epidemiologist Siouxsie Wiles said MIQ processes would be crucial at keeping Omicron out of the community.
"With rapid spread in Australia, the plan to allow NZ citizens to return with no MIQ from 15 January should be immediately postponed to provide certainty to those affected.
"The vaccination requirement for arrivals should be raised to three doses of the vaccine to reduce the risk of Omicron coming here."
He said the traffic light system would also need strengthening in the event of an Omicron outbreak, as its assumptions around immunity of vaccinated people would not hold for the new variant.
Meanwhile New Zealand's medical regulator Medsafe has granted provisional approval for the Pfizer Covid-19 vaccine for children aged 5–11 years old.
Jackson said the arrival of the new variant Omicron had also placed greater pressure on the rollout of vaccines for under 12s.
"The speed at which it hits the community is what overwhelms health services," he said.
"So if you imagine an unvaccinated primary school population, especially if it is a new variant, that would just go crazy."
"The two big things we need to do early next year are vaccinate the kids and to make sure everyone who has already been vaccinated gets a booster."
He said we should also aim for at least 90 per cent vaccination coverage in 5–11-year-olds, as this group would be crucial for New Zealand's overall immunity
"We've hit 90 per cent fully vaccinated, but that still means there's over 400,000 eligibles that are not vaccinated. On top of that you've got 750,000 kids under the age of 12."
"So that's going to be really important for New Zealand's immunity."
While children generally only had mild disease, he said they could take it home and spread it.
"Primary schools in particular, that's a super-spreading setting. There's a primary school in Taranaki where they had 15 cases – that's a real-life example of what happens in schools.
"Kids generally have mild disease but they take it home. And if they take it home to a multi-generational household, and they are interacting with their grandparents, you can get widespread infection."
As the country passed the 90 per cent milestone yesterday, the Green Party has called on the Government to do more to boost the Māori vaccination rate to this level.
Green Party spokesperson for Covid-19 response Dr Elizabeth Kerekere said Māori and Pasifika children also needed to be prioritised for the rollout for children aged 5–11.
"Right now, only 76 per cent of Māori are fully vaccinated across the country, and 86 per cent first dose. The rate is considerably lower in rural areas and particularly among younger Māori.
Ninety-one new cases of Covid-19 were announced in the community.
This includes 55 in Auckland, seven in Waikato, 10 in the Bay of Plenty, one in the Lakes district, two in Northland and 16 in Taranaki.
Yesterday there were 58 people in hospital, with four in ICU. Thirty cases (57 per cent) of those in hospital were unvaccinated or not eligible.
Nine cases (17 per cent) had received one dose and 10 cases (19 per cent) were fully vaccinated. The remaining four cases (8 per cent) were unknown at this stage.
There are 2194 cases of Covid-19 in the community. The number is much lower than earlier figures due to a change in the way the Ministry of Health classifies active and recovered cases.