8 people in Melbourne have now died from thunderstorm asthma

Photo: Dan Kitwood/ Getty Images.

Eight people have died after a thunderstorm in Melbourne triggered a mass asthma emergency across the city.

“One patient continues to receive specialist ICU care in a Melbourne hospital and remains in a critical condition,” the Victorian health department said.

“This was a tragic and unforeseen event and hospitals are continuing to treat 7 people for a variety of respiratory and other related conditions.”

In just five days the death toll has doubled from four.

On November 22 a major storm caused a mass outbreak of an illness known as “thunderstorm asthma”.

Thunderstorm asthma occurs when wind and moisture causes pollen to rupture into small particles that can be inhaled, rather than being filtered out by the nose, causing an asthma attack.

The smaller particles mean it can induce an asthma attack in people who have never had symptoms before. Symptoms include shortness of breath, chest tightness, coughing and wheezing. Anyone with a rye grass allergy is highly susceptible to the illness.

Health minister Jill Hennessy has ordered a review into the response to the mass asthma event which saw hospitals treat more than 8,500 patients.

She said the inspector-general for Emergency Management would review the demand for help and how authorities could better communicate risks to the community.

Thunderstorm asthma was first described in Melbourne in 1987 and has occurred in other parts of the country (south-eastern Australia is particularly vulnerable) and the world, including in England and Italy. Read more on it, and why it happens here.

More to come.

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