Australia is in the grip of a grim flu outbreak, with the number of influenza cases four times higher than a year ago.
Experts believe the rise could be linked to the sudden deluge of wet weather and floods earlier this year when there was an unusually high number of flu cases recorded.
Particularly high rates of influenza have hit NSW, Queensland and South Australia with the H1N1 virus, popularly known as swine flu, and influenza B the most common strains.
Figures from the National Notifiable Diseases Surveillance System show 7931 cases of influenza have been confirmed nationally so far this year, about four times higher than the 1989 cases recorded between January and July 2010.
The number of flu cases seen around the time of the floods in early 2011 were significantly higher than in 2010.
Since May alone, the number of cases have leapt by more than 200 per cent.
There were 2454 cases recorded in June and there have been 1345 so far for July.
The Influenza Specialist Group, a not-for-profit body which raises public awareness about the flu, suggested more increases were likely to be on the way as Australia heads into its traditional peak flu season of August to October.
The group's chair Dr Alan Hampson said while there had been a sharp rise in flu cases this year, it was not a pandemic because no new strain of the influenza virus had been detected.
He said it was hard to know the exact causes of the increase but suggested the floods which hit vast areas of Australia in early 2011 could be to blame.
"I guess one of the possibilities is the weather with the high levels of rain we have had this year could have had some influence on it," he told AAP.
Dr Hampson said wet conditions were ideal for flu virus to survive, with people crowding indoors and not getting as much of immune system-boosting Vitamin D because of a lack of sun exposure.
He urged those most at risk - the elderly, pregnant women and those with underlying health conditions including heart, kidney and lung disease, asthma and diabetes - to protect themselves by having a flu vaccine.
Other ways to avoid the flu include keeping away from crowds and washing your hands regularly.
Bed rest is recommended for those struck down by flu and are suffering from aches and pains, a fever, chills, a cough, sore throat and headache.
It is estimated that influenza and its associated complications kill about 2,500 Australians a year.