It was a shock for many to hear the news four people had died in Melbourne after an unprecedented asthma epidemic took hold of the city following a thunderstorm.

Three patients ended up in a critical condition and around 8,500 others were treated in hospitals. The emergency rooms overflowed and Victoria ran out out of ambulances for an hour.

There’ll be reviews into the deaths and how the state handled the crisis. Experts and authorities have already described it as “extraordinary”, “unpredictable” and “extremely rare”.

“When we’ve had people calling for ambulances — one call every four-and-a-half seconds at the peak. It was like having 150 bombs going off right across … Melbourne,” Victoria’s Health Minister told ABC News.


How it happens

Doctor Megan Howden, a respiratory and sleep physician, explained thunderstorm asthma in a piece for The Conversation. She says the phenomenon happens when there’s a combination of high pollen counts, thunderstorms and warm weather.

“Grass pollen is usually too large to enter the small airways of the lungs and is filtered out by the nose, causing hay fever in those allergic to pollen,” Dr Howden wrote.

“But stormy winds and moisture can cause the pollen to rupture into tiny particles, which are small enough to be inhaled.

“The outflow winds of a thunderstorm then concentrate these tiny particles at ground level, where they can easily enter the small airways of the lungs. This can cause an acute asthma attack in those who are allergic to grass pollens.”

Who it affects

According to Dr Howden, young adults with a history of hay fever are the most likely to be affected by thunderstorm asthma. It is important to understand that you still could have these symptoms even without suffering from regular asthma.z
After a similar situation hit Wagga Wagga in 1997, researchers examined data to investigate the differences between people who suffered thunderstorm and regular asthma attacks.

“They found that 95 per cent of those affected by thunderstorm asthma had a history of hay fever and 96 per cent tested positive to grass pollen allergies,” Dr Howden explained.

“Of those with a history of asthma, only one in four (27 per cent) of affected cases were taking regular preventer inhalers. This was compared with more than half (56 per cent) of the control group.

“This suggests that regular use of asthma preventer medication, at least during spring, may protect those with asthma and grass allergies from thunderstorm asthma attacks.”

The symptoms of thunderstorm asthma

According to Asthma Australia, the symptoms of thunderstorm asthma are the same as typical asthma and include:

  • Difficulty breathing and/or shortness of breath
  • Chest tightness
  • Narrowing of airways
  • Coughing
  • Wheezing (a whistling or squeaky sound in the chest when breathing, especially when exhaling)

If you or someone you know is suspected to be suffering from a life-threatening thunderstorm or regular asthma attack, contact triple-0 immediately. Here are some steps to take while waiting for an ambulance.

Can you prepare for it?

Dr Howden says all asthma sufferers should have a written action plan from their doctor. It is important to know what steps to take if the symptoms of thunderstorm asthma were to escalate.

“In the event of a thunderstorm asthma attack, treatment will be the same as any other acute asthma attack. This usually involves the administration of inhaled medication to dilate the airways, plus an anti-inflammatory medication,” she wrote.

If you’d like to learn more about thunderstorm asthma, these websites have plenty of information: