Social distancing and hygiene measures due to the coronavirus pandemic have dramatically reduced influenza numbers this year but experts expect cases of the flu and common cold to rise as restrictions ease.
Immunisation Coalition chairman Dr Rod Pearce says if people stop social distancing and abiding by advice such as regularly washing their hands and wearing masks, the rates of influenza and other winter viruses will start to rise.
"We expect an increase in the normal winter flu/influenza-like illnesses to happen soon as people come out of lockdown," Dr Pearce told journalists on Tuesday.
Any rise in influenza as restrictions ease could also be a forerunner to a rise in coronavirus cases, the GP said.
"We call it the canary in the coal mine effect, that we'll see other infections increasing and if there's coronavirus around we'll see that increasing as well."
Dr Pearce said cases of the flu are rare in Australia this season, due to the COVID-19 lockdown, restrictions and hygiene measures.
He was involved in testing in a COVID clinic that revealed only one case of influenza among 1000 tests, whereas normally 50 to 60 per cent of people with minor influenza-like symptoms would have positive flu results.
There were only 216 influenza cases in Australia in June, down from 57,842 in June 2019.
So far in July there have been 84 laboratory-confirmed influenza cases, compared to 70,151 for the entire month last year.
Dr Pearce expected there would be a large drop in deaths due to flu this year.
There were 900 deaths linked to influenza last year.
Dr Pearce said there had been a good vaccination rate for influenza this year, with more than 75 per cent of people aged over 65 being vaccinated and children under five getting free flu shots for the first time.