New Zealand is being urged to consider lengthening the time between administering each of the two Covid-19 Pfizer vaccines as research in the UK is proving hopeful a longer time between jabs will better fight off the Delta variant.
Oxford University's Professor Susanna Dunachie, who is the joint chief investigator in the study, this morning told Breakfast they found higher immunity among those who had a 10 week gap between their jabs compared to those with a three week gap - the time trialled by Pfizer.
"The UK took a decision in January, quite brave, to extend that dosing interval and it was partly based on what we know about vaccines and partly to get as many single doses into as many people as possible because we had a big wave coming," Dunachie explained.
"What we did was we studied 503 healthcare workers and we looked at their antibody responses and also a group of white blood cells called T cells that are important in immune response and we compared people who on average had the vaccine three weeks apart with people who had it 10 weeks apart.
"We actually saw a better immune response in the people with the longer gap."
However, Dunachie emphasised that any two jabs were good no matter the gap between, so anyone who has already received two doses shouldn't worry.
"Two jabs definitely better than one," she said.
"With vaccines, one jab often does a lot of the heavy lifting, so you get a lot of protection with one jab. We've got data from the UK showing that one jab is actually quite good at keeping people out of hospital, particularly Alpha variant but even for Delta variant as well.
"The second jab, first of all, increases antibodies, secondly it catches up for some people who didn't respond to the first one, and thirdly it makes it last longer usually but we need to test that in time."
The suggested time between jabs in the UK is eight weeks, but in New Zealand it's currently recommended people wait at least three weeks between doses.
While Dunachie said New Zealand was in a different situation to the UK, which hasn't been able to keep the virus out, but she added that health officials here could consider a lengthier period.
"I'm an infectious diseases doctor and an immunologist so I don't really have all the expertise for policy, you know, taking in the economy and everything else, but I think it is interesting when you've got a country very good at controlling the virus, keeping it out, whether your country might want to consider doing it a bit slower."
In a statement to 1 NEWS, a Ministry of Health spokesperson said the Covid-19 Technical Advisory Group, known as CV TAG, was reviewing emerging international research and its implications for New Zealand.
"They advise that early findings from a small number of well-designed studies show that an extended duration between doses of the Pfizer vaccine gives a robust immune response," the spokesperson said.
"The average time between administering first and second doses is currently just over 25 days.
"The Ministry of Health is aware of numerous other locations where the second dose is routinely delivered longer than three weeks after the first dose, including the UK where the second dose is usually administered 8-12 weeks after the first dose."
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