The government says its experts have considered shortening the gap between Covid-19 vaccine doses for 5 to 11-year-olds but decided against it, saying the current spacing is ideal for children's immune systems.
Most children in that age bracket cannot be fully vaccinated until at least the middle of next month, as the rollout began on 17 January and there is an eight-week wait for the second Pfizer shot.
More than half of Auckland schools reported Covid-19 infections yesterday and almost 2500 active cases nationwide are in children aged under nine.
With under 12s accounting for 14 percent of new cases in the last seven days, a Covid-19 data analyst said the vaccine spacing question must be explored again - and quickly.
Dr Rāwiri Taonui said New Zealand had been slow and conservative in setting its timeframes.
"I don't think the Ministry of Health is treating that issue with enough urgency," he said. "The facts are Pfizer recommends a three-week wait period for the tamariki vaccination, the FDA in the United States does that and so does Health Canada.
"Health Canada has made it as an option, so with parental consent, children can be vaccinated in three weeks.
"Our children are going to school, getting infected, that then becomes a vector for transmitting the virus into the rest of the family and even more widely, so it needs to be treated with some urgency."
He conveyed those concerns at a meeting with Māori Cabinet ministers last week, pointing to evidence that a change could also help boost vaccination rates.
"It's not unlike the booster rollout for for adults, the time setting was four months. When it was shifted to three months the booster uptake in the Māori community since the change was made, there's been an increase of 59 percent and they're starting to catch up."
A much more concerted effort to counter misinformation against vaccination was also needed, he added.
Rates of first paediatric vaccine doses vary significantly: more than 60 percent of 5-11-year-olds are partially vaccinated in Auckland DHB and Capital and Coast, compared to 28 percent in Northland - and only one in five tamariki Māori in that region have had their first dose.
The director-general of health, Dr Ashley Bloomfield, said they had already asked the government advisory group whether a shorter gap would be better. Currently it is eight weeks unless doctors recommend a child gets an earlier second dose, for reasons such as being immuno-compromised.
"They provided advice that we should maintain the eight-week gap," he said.
"Children, because of their much more attuned immune systems, have a much starker response to that first dose, and then also a bigger gap is better for long-term immunity and for reducing the likelihood of some of those rare side effects."
Director of the University of Auckland's Immunisation Advisory Centre professor Nikki Turner agreed the gap should be longer than for adults.
"The eight-week gap is still the most sensible gap for children, even when you've got a lot of Omicron in the community. Children will get good protection from one dose and it's not ideal to bring the gap further forward, so we recommend it only with children who have got very high-risk medical problems.
"They get a good vigorous immune response. And also the second point is that children are at much lower risk of severe Covid disease. We would be hoping that with a longer gap with your first to your second dose, that you'll get better immunity and more durable immunity. So that's why you don't want to rush your second dose if you don't have to."
More than 6600 Covid-19 cases have been reported in under 12s since August, 85 children have been hospitalised and one boy died.
The spacing for adult vaccine doses has also varied, changing from six to three weeks during last year's Delta lockdown.
The director of Wellington's Malaghan Institute of Medical Research, immunologist professor Graham Le Gros, said he understood people's concerns with rising numbers, but the eight-week strategy had benefits for children's long-term immunity shield.
"You've got to remember, you don't want a half-done vaccination programme and then be quite vulnerable for the next few months because you haven't made a really good immune response.
"If they've got a poor immune response for that long memory period for the next six months, you've actually left them off in a worse situation. This is the tricky thing with this virus, you've got to think longer term as well as short term."
RNZ
