Spring brings thunderstorm asthma warning

Asthma sufferers are urged to be on alert for weather changes this spring, following the deadly thunderstorm asthma outbreak last year that claimed nine lives.

Health experts have used the first day of spring to warn people to be prepared for higher pollen counts and unexpected weather changes that could trigger asthma attacks.

Nine people died and thousands suffered respiratory symptoms in what was described as the world's worst recorded asthma thunderstorm in Melbourne last year.

The November storm kicked up dust and pollen, and the moisture in the air from the humid, hot day burst the pollen into hundreds of tiny allergenic fragments, penetrating deep into victims' airways.

NSW Health director of environmental health Ben Scalley said asthma sufferers needed to ensure they proactively managed symptoms and had an asthma action plan in place.

"While Sydney hasn't had a major event like Melbourne, thunderstorm asthma events have been significant in other parts of NSW in recent years, including Wagga Wagga," he said.

Around one in nine adults and one in eight children in NSW have asthma, with 10,000 people admitted to hospital for asthma treatment across the state each year.