Flue season is off to an early start, and so is an annual health surveillance system, FluTracking, which Dr Dalton founded and now coordinates. It is the largest crowdsourcing influenza surveillance system in the world.

"Influenza-like illness in March this year was much higher than normal - it was higher than the peak activity in winter 2018," Dr Dalton said. "While it's impossible to identify the exact cause of spiked flu activity in autumn, one possible factor could be high rates of influenza in travellers returning from the northern hemisphere."

More than 40,000 Australians have reported flu symptoms via the network that last year expanded to cover New Zealand.

The system usually launches in May and can rapidly determine the onset and severity of influenza in both countries, but the system has launched earlier this year to report and track flu activity following the early influx of cases.

The program is a joint initiative of the University of Newcastle, Hunter New England Population Health and the Hunter Medical Research Institute.

Dr Dalton said FluTracking was the only system that proactively engages directly with people in the community to track the frequency and severity of influenza-like illness.

"We rely on data from members of the public to help determine the onset of influenza and better understand the burden and severity of the disease," Dr Dalton said.

"The information captured paints a valuable picture for health professionals, and the community, of flu outbreak zones communicated through a weekly report and interactive map showing affected areas."

The flu vaccine is recommended for all residents, especially the elderly, those with chronic illness, pregnant women and Aboriginal and Torres Strait Islander people.

To find out more and join the FluTracking community go to www.flutracking.net.

The Newcastle Herald