Speaker's Highlight

• Don Sin University of British Columbia, St. Paul Hospital (Canada)
  Kenneth R. Chapman Toronto General Hospital Research Institute (Canada)
• Parameswaran Nair McMaster University (Canada)
  Carolyn Calfee UCSF (U.S.A.)
• Gregory P. Downey University of Colorado School of Medicine (U.S.A.)
  David A. Schwartz University of Colorado School of Medicine (U.S.A.)
• Neil Schluger Tuberculosis Control Branch, California Department of Public Health (U.S.A.)
  Nick Kim Critical Care & Sleep Medicine, University of California San Diego (U.S.A.)
• Nicola Hananiah Baylor College of Medicine (U.S.A.)
  Jae-Joon Yim Seoul National University College of Medicine (Republic of Korea)
• Koichiro Asano Tokai University School of Medicine (Japan)
  Diahn-Warng Perng Taipei Veterans General Hospital (Taiwan)
• Konstantinos Kostikas University of Ioannina (Greece)
  Karin Klooster University Medical Center Groningen (Kingdom of the Netherlands)

• The Impact of Wildfire Smoke on Acute Respiratory Exacerbations

  Wildfire smoke is a serious respiratory health hazard in Australia, where bushfires can affect communities far from the active fireground. Fine particles travel across suburbs, regional towns and major cities, entering homes, schools, workplaces and healthcare facilities. For people with asthma, chronic obstructive pulmonary disease (COPD), bronchiectasis or other lung conditions, a smoky day can quickly become a medical event.

  The danger comes mainly from fine particulate matter, especially PM2.5, alongside carbon monoxide, volatile organic compounds and irritant gases. These pollutants inflame the airways, increase mucus production and reduce lung function. Understanding how smoke triggers acute respiratory exacerbations helps clinicians, families and communities prepare before the next bad-air day arrives.

  Why Fine Smoke Particles Affect The Airways

  PM2.5 particles are small enough to pass deep into the bronchioles and alveoli. They irritate the airway lining and activate an inflammatory response, which can cause bronchoconstriction, coughing, wheezing and chest tightness. People with asthma may notice symptoms within hours, while those with COPD can develop worsening breathlessness and sputum production over several days.

  Smoke exposure can also impair the lungs’ normal clearance mechanisms. Cilia become less effective at moving mucus and trapped particles out of the airways, increasing the risk of infection and prolonged symptoms. This combination of inflammation, mucus retention and reduced oxygen exchange explains why a short period outdoors may have consequences well after the smoke has lifted.

  Who Faces The Greatest Risk

  Children, older adults, pregnant people and anyone with existing respiratory disease are particularly vulnerable. Children breathe more air relative to their body size and may spend time exercising outdoors when conditions look merely hazy. People with cardiovascular disease can also be affected because particulate pollution places additional stress on the heart and circulatory system.

  In Australia, this risk is especially relevant for communities in New South Wales, Queensland and Victoria, where bushfire seasons can stretch across several months. Residents in Canberra have experienced dense smoke drifting from surrounding fires, while people in Sydney and Melbourne may face hazardous air even when flames are many kilometres away. A person does not need to see a fire to be exposed.

  Recognising An Acute Exacerbation

  A flare-up may begin with an unusual cough, throat irritation or a feeling that the chest is tight. Asthma symptoms commonly include wheezing, shortness of breath and difficulty speaking comfortably during activity. For COPD, warning signs can include increased breathlessness, a change in sputum colour or volume, fatigue and a reduced ability to walk or complete routine tasks.

  Urgent medical care is needed when symptoms are severe, rapidly worsening or not responding to the person’s prescribed reliever. Blue or grey lips, confusion, exhaustion, faintness or difficulty speaking in full sentences are emergency signs. In Australia, call Triple Zero (000) for life-threatening breathing problems rather than waiting for a local clinic appointment.

  Smoke Exposure And Emergency Care

  During major fire events, emergency departments and ambulance services may see a sharp rise in respiratory presentations. This surge can occur alongside evacuation injuries, burns, heat illness and anxiety-related breathing complaints, placing extra pressure on regional hospitals. Clear triage is essential because a patient with smoke-triggered bronchospasm may deteriorate quickly.

  Clinicians should ask about the timing and intensity of exposure, indoor air conditions, medication access and previous severe attacks. Pulse oximetry, peak expiratory flow and response to bronchodilator therapy can help guide assessment, although oxygen saturation may appear normal in some patients with significant airway irritation. Carbon monoxide exposure should be considered after time spent near fires, generators or enclosed smoky areas.

  Reducing Exposure At Home

  The most effective immediate measure is to reduce time outdoors when smoke levels are high. Keep doors and windows closed, set air conditioning to recirculate and avoid activities that add indoor particles, such as frying, burning candles or using wood heaters. A properly sized portable air cleaner with a HEPA filter can reduce PM2.5 in a closed room.

  A clean-air room is useful during a prolonged smoke event. Choose a room with few windows, keep the door closed and run filtration continuously if possible. Ordinary paper masks offer limited protection from fine particles; a well-fitted P2 or N95 respirator is more effective when worn correctly, although it may be unsuitable for some people with severe breathing difficulty.

  Preparing An Individual Action Plan

  People with asthma or COPD should review their written action plan before fire season, rather than waiting until smoke arrives. Check inhaler expiry dates, replace missing spacers and make sure repeat prescriptions can be filled if roads close or pharmacies become difficult to reach. Families should know the usual early warning signs and the threshold for seeking help.

  Digital air-quality information can support practical decisions, but readings may vary between stations and suburbs. State fire agencies, environmental protection authorities and health services provide local alerts, while apps such as AirRater can help people track conditions in parts of Australia. During stressful events, households should also be cautious with online financial distractions and risky promotions, including pages discussing online craps in Australian dollars, rather than allowing emergency expenses to compound existing pressure.

  Protecting Children, Workers And Remote Communities

  Schools, childcare centres and sporting clubs should move strenuous activities indoors or postpone them when smoke is heavy. Coaches and teachers need clear procedures for children who develop coughing or wheezing, including access to prescribed reliever medication and a rapid way to contact parents or emergency services. “Smoky” conditions can change quickly, so a blue sky is not always a reliable safety signal.

  Outdoor workers, firefighters and agricultural staff may face much higher cumulative exposure. Employers should provide suitable respiratory protection, rest areas with filtered air and task modifications when conditions deteriorate. In remote and Aboriginal communities, planning must account for long travel distances, limited pharmacy access, communication gaps and the availability of local health workers. Evacuation and respiratory-care plans work best when developed with community leadership before fire threatens.

  Monitoring Recovery After The Smoke Clears

  Symptoms may continue for days after the visible haze disappears. Airway inflammation can remain active, and people with asthma or COPD may experience a delayed decline in lung function. Follow-up is important when reliever use increases, sleep is disrupted, exercise tolerance falls or symptoms recur after initial improvement.

  A post-event review can identify gaps in medication supplies, indoor filtration, transport and communication. Clinicians can use this opportunity to reinforce inhaler technique, update action plans and discuss vaccination, smoking cessation and pulmonary rehabilitation where appropriate. Prevention is more effective when it becomes part of routine respiratory care rather than a once-a-year warning.

  Smoke exposure should be treated as a predictable respiratory risk in Australia, not simply an unpleasant side effect of bushfire season. Check local air-quality alerts, keep essential medicines available, create a cleaner indoor space and follow the person’s written action plan. When breathing becomes difficult or rapidly worsens, seek urgent medical assistance through Triple Zero (000).

  Richard Russell Nuffield Department of Clinical Medicine, University of Oxford (United Kingdom)
• Mona Bafadhel King’s College London (United Kingdom)
  David Jackson Guy’s and St Thomas’ Hospital, King’s College London (United Kingdom)
• James Chalmers University of Dundee (United Kingdom)
  David Price University of Aberdeen (United Kingdom)