NZ could be spared flu epidemic – expert

There’s no guarantee New Zealand will import a ‘‘significant’’ flu epidemic that is ramping up in Australia, but health experts are urging people not to take their chances.

Influenza cases in New South Wales more than tripled between March and last month, with the state recording 1237 flu cases up to April 25. There were 341 cases identified in March. ‘‘The way things are heading, New South Wales will have a significant epidemic outbreak,’’ Professor Ian Barr, a World Health Organisation influenza experts, told the Sydney Morning Herald. He said its peak in the state could come either in August or September.

The dissolution of managed isolation and the gradual reopening of the border means Aotearoa can also expect influenza to circulate for the first time in three winters.

In an ordinary year, flu kills more than 500 New Zealanders, but since the strict autumn Covid-19 lockdown in 2020 it has been almost non-existent. Just eight flu cases were detected in 2020 by the Institute of Environmental Science and Research, and 14 in 2021, mainly from overseas returnees.

In the first four months of 2022, seven cases were detected by ESR’s whole genome sequencers.

All were a variant of the more virulent form of flu known as ‘‘influenza A’’ and all were from Auckland.

ESR senior science leader Dr Sue Huang, who focuses on virology, said while it was possible Aotearoa could experience a spike similar to what NSW is experiencing, it wasn’t a certainty.

‘‘It is also possible New Zealand could experience a situation similar to northern hemisphere countries, with a low flu season. It is hard to predict, because we have a number of factors competing with each other.’’

Huang said a previous survey suggested an average flu season

would infect a third of the population. That population was more susceptible than usual because of the lack of influenza virus circulating in the community over the past two years has created an ‘‘immunity gap’’, she said.

‘‘Vaccination has become the most important tool this year.

‘‘One piece of good news is that our southern influenza vaccine to be used this winter matches well with the current northern hemisphere circulation strains. If we have more people vaccinated against flu, it will help prepare us.’’

Huang said the pandemic had changed people’s behaviour a lot, with more focus on mask wearing, personal hygiene and social distancing, which could dampen down the spread of flu.

A Ministry of Health spokesperson said the influenza vaccination has been available since April 1. It is free for everyone aged 65 years and older, Māori and Pacifika people aged 55 years and over, all pregnant people and other vulnerable groups.

‘‘It is important that we protect those who are most at risk, as well as our health system,’’ the spokesperson said. ‘‘We encourage anyone offered the vaccine at work to take up the opportunity. In addition, there are more options to be vaccinated at both new and traditional venues ...’’

From May 19, pharmacist vaccinators will be able to administer the influenza vaccine to anyone aged 3 years and above – they’re currently restricted to 13 years and above.

‘‘Vaccination has become the most important tool this year.’’ Dr Sue Huang ESR senior science leader