A review into the emergency service response to Melbourne's asthma thunderstorm will examine at least four deaths linked to the rare phenomenon.
Clarence Leo suffered asthma all his life, but nothing could prepare wife Amanda for her husband's reaction to Melbourne's thunderstorm.
"I don't know what was in the air that night but I have never seen him like that, " she said. "He was gasping for air, he opened the window, he threw his seat belt off."
The father-of-two was one of four to die from severe attacks.
"They worked on him for about 45 minutes but it just didn't work," his wife said. "I am glad and thankful that my husband did get help because I saw that other people did not."
A team of experts is desperately trying to determine whether asthma thunderstorm events, like the one linked to four deaths in Melbourne this week, can be predicted in the future.
Government agencies, pollen scientists and the Bureau of Meteorology are meeting on Thursday to discuss Monday's unprecedented event, which overwhelmed emergency services and hospitals.
The other three who died of respiratory issues were 35-year-old Apollo Papadopoulos, law student Hope Carnevali, 20, and Year 12 student Omar Moujalled.
A number of other patients remain in intensive care. One person is in a critical condition.
The perfect storm event saw a high pollen count and thunderstorm conditions combine to produce tiny particles in the air that penetrated deep into people's airways, causing asthma to those who have the condition.
The man who runs Melbourne's main pollen counting station thinks it's possible to develop an asthma thunderstorm forecast given useful data exists from previous events.
"We get those conditions of high grass pollen and thunderstorms quite regularly in Melbourne at this time of year but it's not every time that we get thunderstorm asthma," pollen expert Ed Newbigin from Melbourne University told AAP.
"So there is another factor involved that we don't know (yet)."
Associate Professor Newbigin, who's attending Thursday's meeting, is convinced the state's various monitoring bodies can identify the missing ingredient.
But how reliable a forecasting model would be, and whether it could predict when an event would be as extreme as on Monday, is unknown.
The chairman of the National Asthma Council of Australia, Dr Jonathan Burdon, said the force of the thunderstorm exploded air-borne grass pollens into tiny, but deadly, granules.
"They are small, they get further into the lung and they are really quite allergenic," he said.
"There are now warnings about how health systems across the country would cope with a similar epidemic of what's called 'thunderstorm asthma'.
The NSW President of the Australian Paramedics Association Steve Pearce said southern areas of the state were particularly prone to these type of storms.
"Something on the scale that Victoria was would completely overwhelm what we have in southern NSW in terms of managing emergency calls," he said.
Mr Burdon said sufferers need to be well-prepared.
"Take your treatment regularly as prescribed, seek attention early if you are in trouble and have regular reviews," he said.
"We know that a lot of people with poorly-controlled asthma in Australia don't take their regular medication regularly and they are at higher risk of having an asthma attack."
The tragic fallout from the storm has overshadowed the fact that deaths from asthma in Australia have actually fallen dramatically over the past three decades, from almost 1,000 to around 400 a year.
Dr Burdon said while it was a positive trend, there was no room for complacency.
"We need to reduce the death rate. Deaths from asthma are mostly preventable."
Asthma thunderstorm reviews
The Inspector-General for Emergency Management is leading an overarching review that will examine how Ambulance Victoria and emergency services responded and how the community was notified of the unfolding crisis earlier this week.
The review will also investigate the four deaths.
Ambulance Victoria will separately conduct an internal review.
A Department of Health spokesman on Thursday told AAP he was unable to give a running tally of the number of deaths following Monday's rare phenomenon that led to an unprecedented 1900 emergency calls in five hours.
At one point there were 140 "code one" cases occurring at the same time.
Pollen counts in Melbourne have been at low or moderate levels since Tuesday.
The director of respiratory and sleep medicine at Austin Health, Professor Christine McDonald, says because asthma is an inflammation of the airway "it's not going to suddenly disappear as the weather features change".
Professor McDonald told 3AW if people experienced lingering symptoms they should seek treatment.
The Austin Hospital still has one patient in intensive care.