Thunderstorm asthma epidemics in Melbourne almost always occur in November. There have been four recorded major epidemics previously reported: 8th November 1987(1 death); 29th November 1989 (no deaths); 25nd November 2010 (no deaths); and 21st November 2016 (At least 4 deaths so far).
They usually follow several days of elevated pollen counts and warm conditions followed by a sudden cool change causing rupture of pollen grains into tiny particles that can be breathed into the lower airways and cause asthma.
The great concern is the group of patients with hay fever who have never reported asthma symptoms, those who can have their first attack in these thunderstorm conditions.
We do not have all the data in, but 2016 appears by far the most severe epidemic of thunderstorm asthma both in fatalities and sheer numbers of presentations.
If you have springtime hay fever (sneezing, running or blocked nose and itchy eyes) during spring, you are at risk from thunderstorm asthma, even if you have never previously from suffered asthma. My five recommendations are as follows:
1. Be aware of thunderstorm warnings in spring and summer and monitor the pollen counts (the Bureau of Meteorology and Melbourne Pollen Count both have excellent smart phone apps and twitter feeds). The Government is working toward a co-ordinated warning system to be in place by next pollen season.
2. If there is a thunderstorm warning in spring or summer, stay inside with windows closed or in air-conditioned areas where possible (this will reduce your allergen exposure).
3. If you usually suffer from asthma, make sure you are taking your preventer regularly and have your reliever to hand and have an asthma management plan. If you begin to experience breathing difficulties, activate your action plan. Dial 000 for ambulance if you have severe shortness of breath. A notable feature of what we have observed so far is that very few asthmatics who were taking regular preventers have required admission to hospital.
4. Even if you have never experienced asthma before, if you are a usual hay fever sufferer, in thunderstorm conditions, you may experience asthma for the first time. Coughing, chest tightness, wheezing (a whistling musical sound in your chest when you breathe) or shortness of breath may be asthma. These symptoms may not be familiar to you but could be serious - seek medical attention.
5. In the future, after this catastrophic event, if you are a springtime hay fever sufferer, I believe the medical profession will have a much lower threshold for putting you on an asthma preventer during the pollen season (Grand Final Time in Melbourne until the end of the year) or providing you with asthma reliever medication for emergency. Further research will need to focus on this at-risk group so we can give firmer, more evidence-based recommendations.
Dr Michael Sutherland is a Respiratory Physician and Allergist at the Epworth Hospital and published a report on the 2010 Thunderstorm Asthma epidemic and has ongoing research collaborations in this condition.