Health officials are actively considering whether to expand access to second Covid boosters.
It comes as hundreds of thousands of eligible seniors are still being urged to get their extra shot.
Currently, health authorities say only people at risk of severe illness from Covid-19 are eligible to receive a second booster. These include:
- People aged 65+
- Māori and Pasifika aged 50+
- Residents of aged care and disability care facilities
- Severely immunocompromised people who have already received four doses
- People aged 16+ who: live with multiple comorbidities, or have a disability with significant/complex health needs, or have a medical condition that increases their risk of a severe breakthrough Covid infection
A second booster is also available for people aged 50 and over, and health, aged care and disability workers who are aged 30 and over.
Only 42.6% of eligible over-50s have taken up the second booster - first made available in June - but some may be ineligible due to a recent first booster or Covid-19 infection.
To receive a second booster, people must be six months out from their first booster shot, and also three months out from any prior Covid infection.
Will eligibility be expanded?
With a bump in Covid-19 case numbers in the past month, some have questioned whether vaccine eligibility should be expanded.
On Monday, the Ministry of Health said there had been 20,802 new cases in the previous week.
Second booster shots are more widely available overseas - including in Australia where over-30s have been eligible for a fourth dose since July.
When expanding eligibility, Australian health officials said younger adults can choose to "to reduce their risk of infection" but that overall impact on population-wide transmission was likely to be "limited". It said older people and at-risk groups needed another booster with greater urgency.
Back home in August, the Ministry of Health's vaccine technical advisory group recommended against allowing over-30s to get a second booster.
At the time, it wrote that it was "unclear whether the benefits outweigh the risks".
"An individual's personal decision to have a second booster dose may be influenced by concern that an infection might result in time off work and/or be associated with prolonged symptoms," the group said.
"However, the available data in this age group suggests that the impact of a second booster dose on infection, transmission and maintenance of healthcare capacity is likely to be limited."
But three months later, the ministry's advisory group has given updated advice on second boosters in the past several weeks.
In a statement, Covid-19 Response Minister Ayesha Verrall said health officials were now actively reviewing the advice to potentially expand eligibility.
"The Ministry of Health has received advice from the vaccine technical advisory group and is still currently assessing the eligibility criteria for the second Covid-19 booster," she said.
"I am still awaiting their advice before making any further announcements."
She said the Government had so far been prioritising vulnerable groups in the roll-out.
"We need to ensure changes to eligibility for vaccines balance any risks with the potential gain of offering additional protection."
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