A New Zealand health expert has called for caution as nations move quickly to find a COVID-19 vaccine, saying authorities should avoid what happened in Samoa in 2018 when the incorrect administration of the measles vaccine led to people shunning treatment.

Dr Dr Nikki Turner from Auckland University's Immunisation Advisory Centre told Radio New Zealand in an interview that the registering of a COVID-19 vaccine in Russia recently – which is yet to be subject to the critical stage three trials – could erode public trust if not done well.

"There's a huge risk. There are vaccines out there in the international market that I wouldn't touch with a barge poll and it is really important scientists publish their data, that the data is transparent, fully transparent, and people can come in from the outside and critique the data."

Two years ago two infants died in Samoa after two senior Ministry of Health [MOH] nurses incorrectly administered the measles vaccine. The two nurses were jailed for up to five years in August last year, though the long-term impact of the saga was the public shunning the Ministry’s measles vaccination program due to fears triggered by the deaths.

Dr Turner told Radio New Zealand that health officials in New Zealand could ensure a repeat of Samoa’s experience is avoided by ensuring the public had “high levels of trust” in them, notably marginalised groups.

"So if you're already suspicious about your government or your health authorities, and then there's some significant human error, then that'll have more impact on people's confidence.

"Whereas if you have a community that has walked together, understands that science is really good, but not perfect, and human error happens, then the community can rise above errors better."

Another health expert, Professor Michael Baker, told Radio New Zealand that “while a 60 per cent uptake could work, 80 per cent would provide the best chance of this country achieving herd immunity.”

Professor Baker said getting high numbers could be a challenge, but it should not be difficult to raise public confidence in such a vaccine.

"Given the vaccine is going to be used and probably being given to hundreds of millions of people, perhaps billions of people around the planet, there'll be a huge amount of data on how effective it is and if there are any safety concerns."

However, he maintained that proper training in the administration of the vaccine is essential, as this would ensure that the mistake such as that experienced in Samoa in 2018 is avoided.

University of Otago infectious diseases expert, Professor David Murdoch, who was advising on the development of the Oxford vaccine, told Radio New Zealand that it is one of those showing the most promise.

And while phase three trials are close to being concluded, he expressed confidence that “corners were not being cut and safety was not being compromised.”

"It's actually in preparation for that, gearing up, factories gearing up, the facilities and the technology, so that if it is going to be licensed that they are ready to go, rather than waiting until it is licensed, then starting to do that. Getting some of the accreditation paperwork underway early so that when all the appropriate studies are done, that we're already part way along that journey."