Asthma and hay fever sufferers across Victoria are being urged to stay vigilant and take precautions as potential thunderstorms and high pollen levels on Wednesday pose an increased risk of thunderstorm asthma.
According to VicEmergency there is a moderate risk of epidemic thunderstorm asthma in the Central, North Central, North East, South West, Wimmera, South and West Gippsland and East Gippsland districts.
Melbourne and greater Melbourne are included in these areas.
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The combination of high grass pollen levels and a forecast chance of thunderstorms in the afternoon and evening has caused the risk level to increase.
Epidemic thunderstorm asthma is more likely to occur during grass pollen season, which runs from October 1 to December 31.
People can start experiencing breathing difficulties when pollen grains get swept up in wind and burst, releasing tiny particles just before a storm.
The particles are so small that they can go deep into a person’s lungs, making it hard to breathe.
Asthma symptoms include wheezing, shortness of breath, chest tightness and coughing.
Severe thunderstorm asthma symptoms can be triggered in people who have hay fever or asthma, and even people who don’t have a history of the chronic lung disease.
Those at an increased risk should avoid being outside during thunderstorms, particularly in the wind gusts that occur before a storm, and instead remain inside, with closed doors and windows.
If an air conditioner is on it should be turned to its recirculate setting.
People who have preventative medication should also take it as directed, even if they are not experiencing symptoms.
On November 21, 2016 Melbourne was hit with an unprecedented outbreak of thunderstorm asthma triggered by high pollen, strong winds and moist air.
Ten Victorians died, and about 14,000 people were treated in hospital.
Additional information about thunderstorm asthma can be found on the Better Health website.
Temperatures are expected to soar into the mid-30s across many parts of Victoria on Wednesday, resulting in a total fire ban in the Mallee region.
Northerly winds are set to increase to 30 to 45 km/h in the morning before moving south to southwesterly and slowing down in the evening when a cool change is forecast.