Airborne allergens including pollen, dust mites, mould, and animal dander.
House dust mite (HDM) allergy is the most common cause of perennial (year-round) allergic rhinitis and allergic asthma worldwide. The allergens are proteins in mite faeces and body fragments — not the mites themselves.
Pollen allergy — commonly called hay fever or allergic rhinitis — is a seasonal immune response to airborne pollen from trees, grasses, or weeds. It affects up to 30% of adults and is the leading allergic disease globally.
Pet dander allergies — most commonly to cats and dogs — are triggered by proteins in animal skin cells (dander), saliva, and urine, not by pet fur itself. Cat allergy is about twice as common as dog allergy and produces particularly potent allergens.
Mould spore allergy causes both seasonal and perennial allergic rhinitis and asthma. Key moulds include Alternaria, Cladosporium, Aspergillus, and Penicillium — each with distinct seasonal and indoor exposure patterns.
