Third person dies from Melbourne's thunderstorm asthma

Thunderstorm asthma happens when a thunderstorm, sudden change in humidity, a northerly wind change and high pollen count are combined.

A third person appears to have died during Melbourne's thunderstorm asthma event earlier this week.

Friends of a 35-year-old man have paid tribute to him on Facebook with one writing he "passed away from an asthma attack" on Monday after paramedics worked to revive him for 50 minutes.

Ambulance Victoria won't confirm the reports because they say an official review is underway.

Thunderstorm asthma is a rare spring event that happens when a thunderstorm, sudden change in humidity, a northerly wind change and high pollen count are combined. This perfect storm causes pollen "packages" to be dispersed.

Victoria ran out of ambulances on Monday night as emergency calls jumped a staggering 450 per cent, and several hospitals enacted disaster management plans to cope with floods of patients struggling to breathe.

The thunderstorm asthma event led to the deaths of at least two people. A number of other patients remain in intensive care and one person is critical, Health Minister Jill Hennessy said today.

A spokesman for Ambulance Victoria today said the organisation wouldn't confirm details of individual cases but instead would provide information to a review being conducted by the state's Inspector-General for Emergency Management.

Earlier today the family of a 20-year-old woman who died during the thunderstorm asthma event said patients should be told if an ambulance is delayed so they can drive to hospital themselves.

Hope Carnevali, 20, was one of those who died. Photo / Facebook

Hope Carnevali, 20, died on Monday night while waiting 40 minutes for an ambulance during the unprecedented asthma outbreak.

Another Melbourne resident died after suffering respiratory issues. He's been named as Year 12 student Omar Moujalled in media reports.

Hope's uncle, John Carnevali, told 3AW today "we don't blame the paramedics because they do a fantastic job".

"It's just that the system needs to be changed ... to let people know, if they can't get there in a certain time and they think it's pretty bad, drive yourself to hospital if possible."

Hennessy says there'll be a wide-ranging review of the storm and its health impacts with the government hoping to better predict future events.

The review into how Ambulance Victoria and all emergency services responded will be conducted by the Inspector-General for Emergency Management.

It will examine how the community was informed of the unfolding crisis, including Mr Carnevali's suggestion regarding better advice on ambulance response times.

- AAP