Infectious diseases expert Professor Peter Collignon from the Australian National University (ANU), has called for a review of Australia's flu vaccine policy in light of new research.
"What was a bit surprising when we looked at some of the data from Canada and Hong Kong in the last year is that people who have been vaccinated in 2008 with the seasonal or ordinary vaccine seemed to have twice the risk of getting swine flu compared to the people who hadn't received that vaccine," he said.
ANU microbiologists say it is the opposite of what vaccines should do.
Professor Collignon says the findings of the study also highlight the benefits for healthy people who are exposed to some illnesses.
"Some interesting data has become available which suggests that if you get immunised with the seasonal vaccine, you get less broad protection than if you get a natural infection," he said.
"It is particularly relevant for children because it is a condition they call original antigenic sin, which basically means if you get infected with a natural virus, that gives you not only protection against that virus but similar viruses or even in fact quite different flu viruses in the next year.
"We may be perversely setting ourselves up that if something really new and nasty comes along, that people who have been vaccinated may in fact be more susceptible compared to getting this natural infection."
Professor Collignon says that in light of the study, the Australian Government and health policy makers need to look at whether vaccines actually do more harm than good, particularly in people who otherwise have not got risk factors.
Authorities however say "vaccines good, blah, blah - no vaccines evil, blah, blah"