Prime Minister Jacinda Ardern has welcomed Medsafe's "very carefully considered" provisional approval of the Pfizer/BioNTech vaccine for children aged 12 to 15.
Previously it had only been approved for those aged over 16, but Pfizer trials in April showed 100 per cent efficacy for those aged 12 to 15. Canada, the United States, Europe, the United Kingdom and Japan had all since approved it for that age group.
Medsafe's approval process was very carefully considered, with safety the key priority using "the most up-to-date scientific and medical data available", Ardern said.
There were enough vaccines to vaccinate the younger group and nobody would miss out, Ardern said.
While it was too early to outline details, schools would likely be part of the rollout, she said. There was also the possibility this age-group could be vaccinated at the same time as other whānau members.
The next step is for the Government to review advice from the Ministry of Health about Medsafe's "decision to use", with a decision later this month. Until that decision is made, none of the around 265,000 children aged 12-15 would be given the vaccine.
In terms of vaccination group sequencing, Ardern said officials were working through the details but indicated they would be part of group 4 with exceptions around families getting vaccinated together.
Cabinet so far has been "very inclined" to vaccinate those at most risk of catching Covid-19, such as MIQ and border workers and their families, Ardern said.
That meant children 12 to 15 in those categories could be given priority to be vaccinated immediately following Cabinet approval.
Director general of health Ashley Bloomfield said trials were also under way around children 6 to 11 being vaccinated, which the Ministry of Health was keeping a close eye on.
Pfizer trials with those aged 12 to 15 have showed a robust antibody response and tolerable side effects consistent with those seen in adults aged 16 to 25.
The trials included 2260 adolescents in the United States, with and without evidence of prior SARS-CoV-2 (the virus that causes the disease) infection. There were 18 cases of Covid-19 in the placebo group and none in the vaccinated group.
A strong antibody response was observed in a subset of adolescents one month after the second dose.
Further clinical trials have commenced in children aged 5 to 11 and are expected to begin in younger children aged 2 to 5 in early April, followed by ages 6 months to 2 years old.
The most important part of the Government's early decision-making has been the independent approval process from Medsafe, Ardern said in response to parents who could be nervous about children being vaccinated.
Asked if New Zealand should follow WHO guidelines and provide vaccines to countries in need rather than vaccinating non-priority groups - such as children - Ardern said that was reflected in New Zealand's rollout not ramping up until the end of the year.
While Covid-19 had not generally affected children as severely as it has adults, there had been cases internationally of children getting sick from the virus, Ardern said.
"In addition, children have been shown to transmit the virus, so being able to vaccinate them helps protect the wider community.
"Put simply - when our children are vaccinated, their teachers, friends, siblings, parents and grandparents are more protected from the virus too. So it's in all of our interests for this group to get the vaccine," Ardern said.
A decision on Johnson & Johnson's Janssen vaccine is also expected within the next fortnight.
Janssen Pharmaceutica, a Belgium-based division of Johnson & Johnson, was one of the four vaccine providers with which New Zealand had signed in-principle purchase agreements – in this case covering up to 5 million vaccines.
Ardern previously said the Pfizer vaccine remained the predominant Covid-19 shot that Kiwis could expect to receive this year.
However, the Janssen vaccine has been regarded as a potential "plan B" if there are any issues with Pfizer stocks.
Bloomfield previously said AstraZeneca was also in the approval process, namely because of issues around manufacturing, and Novovax was on a "slower timeframe".
Ardern received her first Covid vaccine at Manurewa Marae in Auckland on Friday, saying it was "pretty pain-free".
On Thursday Bloomfield unveiled the general public Covid vaccine rollout plan, starting with people over 60 from July 28.
It would then progress down in age brackets with those 55 and over able to book from August 11. People 45 and older should be able to book from mid-to-late August, and people over 35 should be eligible about a month later.
It will likely open up for the rest of the population in October.
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