More than 21,000 Australians, mostly young and healthy, have been struck down by the flu so far this year – that’s a 36% increase on the same period last year.

Swine flu is the most common flu virus type, the people behind the numbers – Influenza Specialist Group (ISG) – say.

As of August 11, Queensland has been hardest hit with 6890 cases. In NSW, 6652 cases of influenza have been reported, with Victoria reporting 2715 cases, South Australia 2023, Western Australia 1906, the Northern Territory 339, Tasmania 218 and the ACT 317.

Young people aged 24-64 face the greatest risk, ISG warned.

“People tend to think of the flu as an illness that has its worst impact on the elderly,” Dr Alan Hampson said. “Many of those affected are not elderly people.”

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