The heat kills more Australians than the road toll according to a coalition of health bodies working to increase awareness of the risks of extreme heat.
The Australian Medical Association, the Climate and Health Alliance and the Climate Commission issued a health alert today to urge people to take care of themselves on hot days, to be aware of the dangers of extreme heat and follow health and medical advice on how to stay cool.
Liz Hanna, Climate and Health Alliance President and Convenor of the Climate Change Adaptation Research Network - Human Health at the Australian National University said most people aren't aware of the dangers of the heat.
She said the frequency of heat related illnesses would only increase as the temperatures experienced in last week's heatwave become the norm.
"Temperatures in the high 40s will become the norm as average temperatures continue to grow due to climate change," Dr Hanna.
She said while infants, small children, the elderly and people with existing heart conditions were at most risk during extreme heat, anyone who was exposed to the heat directly, such as people working outside, was vulnerable when temperatures exceeded 40 degrees.
"There's an attitude that Australia is hot, this is summer, just get used to it
"But the heat we're experiencing now is extraordinary, so it's important to remember to keep to shaded areas and stay hydrated on extremely hot days."
Australian Medical Association president Steve Hambleton said Australia would probably experience more heatwaves in coming years.
"Recent comprehensive analysis has shown that there is a direct correlation between increased death rates in hospitals and high temperatures," Dr Hambleton said.
He said it's vital that people at risk keep hydrated, stay in the shade and make sure they are in an area with moving air.
Dr Hambleton also recommended taking several showers during the day to cool down.
"Average temperatures are rising all over the world we need to include extreme heat into our emergency plans.
"Heat can cause health problems, which people may not anticipate, such as salmonella poisoning, because food spoils more quickly on hot days."
Climate Commissioner, Roger Beale said heatwaves have killed more people than any other natural disasters.
"In the 2009 Melbourne heatwave, 173 people died in the Black Saturday bushfires, but more than 370 people died in the heatwave that week," Mr Beale said.
"The work we have done suggests that the killer heatwaves are the ones which happen suddenly, the heat is sustained for some time and when it doesn't cool down during the night; those are the heatwaves during which deaths most frequently occur."
Mr Beale said people who are socially isolated, mentally confused or work in confined spaces such as roof cavities or radiant heat environments where they are surrounded by concrete or rock are also vulnerable to heat stress.
"The key is to keep hydrated, keep cool and if you think someone in your family or your neighbours may need some help check on them."
Spokeswomen for the Royal Prince Alfred, Westmead and Liverpool Hospitals said the emergency departments at those hospitals did not record spikes in patients with heat related illnesses.
"But it is often hard to pin point which illnesses are heat related and which aren't," the spokeswoman for Westmead hospital said.