Average number of asthma visits to A&E was nearly 18 per day during periods with thunderstorms
By
A new study has revealed how thunderstorms can trigger sharp increases in asthma-related emergency department visits. Known as ‘thunderstorm asthma’, the condition is a well-documented environmental phenomenon internationally – back in 2016, more than 9,000 individuals received urgent medical care for thunderstorm asthma after a storm hit Melbourne.
However, until now, studies in the US in areas with high pollen – believed to be a factor in inducing thunderstorm asthma – have been limited.
According to the World Allergy Organisation, thunderstorms are considered a risk factor for asthma attacks in individuals suffering from a pollen allergy.
Enjoying this article? Check out our related reads:
In the new study, researchers analysed 4,439 asthma-related emergency department visits across three US hospitals from January 2020 to December 2024. Using meteorologic records, they identified 38 thunderstorm days during this period.
They found 14 per cent of all asthma-related visits (627 cases) occurred on just 38 storm days, representing just two per cent of the calendar days in the study period. In addition, the average number of asthma visits was nearly 18 per day during thunderstorms, compared to just three on non-storm days.
‘These results confirm that thunderstorms can pose a serious health risk for people with asthma, even in the United States,’ said lead author of the study Diala Merheb. ‘Because storms are unpredictable, patients and healthcare providers should include storm-specific precautions in asthma action plans.’
Researchers note that storm-related surges in asthma place a significant burden on emergency departments. By recognising the connection between thunderstorms and asthma, communities and healthcare systems can develop strategies to help protect vulnerable populations.
The exact mechanism for thunderstorms worsening asthma isn’t known, but one theory links the phenomenon with cold air downdrafts. During thunderstorms, these downdrafts can produce winds which drive pollen grains and fungal spores up into the air. Wind, humidity and lightning can then break up particles into a smaller size so that they can enter the nose, sinuses and lungs.
Studies suggest that pollen levels spike around 20-30 minutes into a thunderstorm, with younger people most affected.
