Thunderstorm asthma shows 'worrying' trend

Four in 10 people experiencing thunderstorm asthma symptoms had not been diagnosed with asthma yet most had suffered hay fever prior to last week's freak event in Victoria, an Asthma Australia survey has found.

Early results from the online survey conducted following the deadly thunderstorm asthma event have highlighted a "worrying" lack of awareness about the common disease of the airways.

Of the first 2000 respondents who did have an asthma diagnosis, 68 per cent had been prescribed preventer medication but only 29 per cent took it every day.

Preventer medications reduce the underlying inflammation of the airways, protecting people from symptoms and potentially serious asthma attacks when exposed to triggers like pollen.

Asthma Australia CEO Michele Goldman says the early results are proof that more needs to be done to improve asthma awareness and management.

"Asthma is a common condition that can be life threatening. Not only is good management essential for people diagnosed with asthma, such as taking preventer medication as prescribed, it is also vital that everyone is aware of asthma - how to spot the symptoms and what to do in an asthma emergency," Ms Goldman said in a statement on Friday.

Victoria's freak thunderstorm asthma event killed eight people and thousands were hospitalised.

Jo Foster was one of the 8500 Victorians who ended up in a hospital emergency department last Monday - unaware she had asthma.

She started suffering from shortness of breath and a persistent cough and says he felt like her body "forgot how to breathe".

"I have been to the GP twice. My lung capacity is still reduced so I'm now on steroids. Today is the first day since then I have not been coughing continually," Ms Foster said.

Asthma Australia advises anyone affected by thunderstorm asthma to speak to their doctor to see if they would benefit from preventer medication and obtain an asthma action plan for emergencies.