The Science Behind Thunderstorm Asthma, Possibly Linked to 6 Deaths

Australian officials reported six deaths possibly linked to the event.

It may sound like science fiction, but the phenomenon has been documented in multiple countries and is believed to have caused thousands of other asthma attacks.

What Is Thunderstorm Asthma?

Thunderstorm asthma is is triggered by huge amounts of pollen released before or after a major storm, triggering asthma attacks. A 2006 study explained what causes the phenomenon. "The weather, such as rain or humidity, may induce hydration of pollen grains and sometimes also their fragmentation, which generates atmospheric biological aerosols carrying allergens," the study authors wrote.

How Many People Were Affected in Australia?

At least six deaths may be linked to the thunderstorm asthma event, and five patients remain in the intensive care unit, including three patients who are in critical condition, department officials said in a statement.

"Ambulance paramedics, emergency services staff and dedicated doctors, nurses and pharmacy staff saved the lives hundreds of Victorians who received treatment as a result of their symptoms," officials said in a statement today. "Asthmatics should continue to take medication as usual, to seek help as required from their [general practitioner] or a health professional and to stay inside when dust or pollen is irritating."

How Often Has It Occurred?

The phenomenon remains rare but, according to medical literature, has occurred in a number of countries besides Australia — including Italy, the United Kingdom, Canada and the U.S. (in Atlanta). One of the first known events occurred in 1983 in Birmingham, England, when 26 asthma attacks were recorded after fungal spores were released during a thunderstorm.

How Deadly Is Thunderstorm Asthma?