Thunderstorm asthma

One of the most common triggers or allergens for people with asthma is pollen.¹

Pollen can come from grasses, leaves, some flowers and trees. If you have an allergic reaction to pollen, it can affect your breathing.

Some types of thunderstorms can cause pollen to spread in large amount very quickly, putting people with allergies and asthma at risk.²

Thunderstorm asthma is a term that describes an event where there are high levels of grass pollen combined with a thunderstorm, which can result in a large number of people experiencing asthma symptoms very quickly.

During a thunderstorm, the rain and high winds can cause pollen grains to burst, spreading tiny particles of pollen in large amounts across wide distances.³

When breathed in, these particles affect the lungs and cause asthma symptoms.

In November 2016, the largest ever global thunderstorm asthma event was recorded in Australia. Over 30 hours there was a 672% increase in hospital admissions due to asthma symptoms across Melbourne and Geelong.⁴

As a result of the 2016 event, thunderstorm asthma warnings are now included on Victoria’s emergency information website, VicEmergency. There are also websites dedicated to monitoring and reporting pollen counts in Melbourne.

Thunderstorm asthma events have been reported across Australia and around the world.⁵

According to Asthma Australia, people most at risk of being affected by thunderstorm asthma are people who have:

• seasonal hay fever
• current asthma
• a history of asthma
• undiagnosed asthma.

“Very severe asthma attacks triggered by thunderstorms are more likely in people who have asthma as well as allergic rhinitis (hay fever), especially if their asthma is not well controlled, or they are not taking regular preventer medication for their asthma,” says Associate Professor Debbie Rigby, clinical executive lead at the National Asthma Council Australia.

“And people with hay fever and an allergy to ryegrass pollen may be at risk of thunderstorm asthma even if they’ve never had asthma symptoms before.”

Like other forms of asthma, thunderstorm asthma can cause:

• wheezing
• difficulty breathing
• persistent coughing
• chest tightness.³

“If you have hay fever and have ever developed chest tightness, a cough or wheezing in springtime, you may also have asthma,” says Rigby.

While it might be impossible to avoid altogether, there are some ways to decrease your exposure risk to pollen as a result of thunderstorm asthma:

• Use your preventer medication regularly, especially during the spring season.
• Check pollen levels daily and avoid being outside on high-pollen days where possible.
• Manage existing asthma well with your asthma action plan and prescribed medications.

“The best defence that Australians with allergies and asthma can have as they head into thunderstorm asthma season is good day-to-day control of their asthma,” says Rigby.

If you or anyone you know is having difficulty breathing, call triple zero (000) or go to the nearest emergency room.

The National Asthma Council Australia offers information and support for those living with asthma. This includes asthma first aid instructions.

Asthma Australia offers support and advice online or by phone on 1800 278 462. Their Asthma Action Plan is available for download.

VicEmergency provides live asthma thunderstorm warnings for people living in Victoria. Melbourne Pollen has real-time information on the pollen count and forecast across the state.