Air New Zealand says more than three-quarters of its frontline employees are fully vaccinated against Covid-19.
The company says 79 per cent of its border workers have had at least one dose of the vaccine, and 76 per cent have had both.
About 3800 border workers still haven't had a single vaccine jab yet, nor have about half of the 50,000-odd household contacts of border workers who are meant to be at the top of the priority queue.
And the latest figures suggest there are about 1100 workers at the border who are not getting tested within the required timeframe.
Epidemiologist Professor Michael Baker said it was "hugely concerning" such a large proportion of the border workforce and their households remained unvaccinated.
"Having them vaccinated at the frontline is critical to maintaining elimination because it sets up a safety barrier at the border."
For that reason all border workers, not just those in MIQ, and their households should be getting vaccinated before people in other priority groups such as healthcare workers or the elderly, he said.
There are an estimated 13,000 border workers over a fortnightly period. That includes about 4500 workers in MIQ facilities, 95 per cent of whom have had two doses of the Pfizer vaccine.
Of the remaining 8500 non-MIQ border workers, about 4500 of them are fully vaccinated, while 200 have had one Pfizer jab.
That leaves about 3800 border workers at airports and sea ports, or transporting to and from there, who are yet to have a single vaccine dose.
Director general of health Ashley Bloomfield wouldn't say if he was concerned, saying instead his main concern was about people in general getting vaccinated.
He stood by his comments earlier this week that we were only at "the end of the beginning".
"If you look internationally, we can see there are a couple of developments. One is those countries and jurisdictions that have previously done well in keeping the virus out [but are no longer do so] - the Singapores, Fijis, Taiwans and arguably Melbourne over the last couple of weeks," he said.
"It's an unpredictable virus, and you just cannot let your guard down. So that rhythm will continue."
Bloomfield said the emergence of new variants that might be more infectious and deadly would create new challenges.
"Even with vaccination, and even with reduced rates of infection around the world, we will still need those other public health measures.
"We'll need to keep adapting those. But the core public health measures around distancing, use of masks, and good infection prevention control will continue to be the same.
"We have done well, we've continued to do well, but we shouldn't can't take anything for granted because the pandemic is still in full flight internationally."
Additional reporting: RNZ