Health authorities are bracing for a flu epidemic this winter after evidence emerged that people are shunning vaccination in the wake of the spike of bad reactions among young children.
A Westpoll reveals a loss of public confidence in flu vaccinations following the halt of the State's immunisation program for children under five.
Almost 70 per cent of parents questioned said they would not immunise their young children against flu and half of them had changed their mind because of the recent alert.
And one in 12 people aged over 60, who are also vulnerable to serious flu illnesses, said they had decided against getting the vaccination or had doubts about it.
Australian Medical Association WA president Gary Geelhoed said there was a risk of not only a flu epidemic but a resurgence of human swine flu strain H1N1.
"It's certainly true that it could be much worse this winter," he said.
"Flu this year will hopefully be no worse than other years, but it's the second year of the so-called swine flu or H1N1. It could be much, much more serious this year."
Professor Geelhoed said he hoped the Federal Government would re-start seasonal flu vaccine programs for under-fives.
They were stopped nationwide in April after hundreds of WA children who had their vaccination suffered unexpected bad reactions, including 57 with convulsions.
WA Health Minister Dr Kim Hames said it was concerning that people were reconsidering whether to have the vaccination, but he understood why they were worried.
"It is virtually impossible to predict the severity of a flu season from one year to the next," he said.
"We usually have an uptake of about 35 per cent for our under-fives influenza vaccination program, so with that figure expected to be lower we may see more illness around."
Professor Geelhoed said he was not surprised by the Westpoll findings and warned that fewer immunisations meant more vulnerable people would be at risk.
"If immunisation rates for flu drop, it's going to circulate a lot more in the community and those healthy adults who are thinking about not getting it should remember they have a certain responsibility for other people, the very young in the community and the very old," he said.
The Westpoll, which interviewed 402 adults last week, found that of those who had intended to have the flu vaccination this winter, 8 per cent said they definitely would not.
A further 6 per cent were reconsidering their decision to be vaccinated.
Parents of children aged under five were most worried by the recent scare, with 33 per cent saying they would definitely not have their children vaccinated against flu despite previous plans to do so.
A further 34 per cent said they had not intended to give their child the vaccination anyway.
Forty-one per cent of people over 60 said they had not planned to be vaccinated.
Of those who had planned to be immunised, 8 per cent had now decided not to or were reconsidering.
Flu vaccine programs for children under-five remain suspended nationwide as health authorities still try to determine the cause of the bad reactions.
Dr Hames said research so far suggested the more severe reactions were limited to one year of seasonal flu vaccine, and potentially one brand - CSL's Fluvax.
He said other influenza vaccines were still safe and urged people to speak to their doctor about other options.