Mould Allergy

Also known as: Fungal allergy, Alternaria allergy, Mold allergy

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.

Symptoms

Airways & Breathing

Rhinitis
Sneezing
Asthma — often severe with Alternaria exposure

Skin

Itchy eyes
Worsened eczema

Systemic / Other

Fatigue

How It's Diagnosed

Skin prick test to a mould panel (Alternaria, Cladosporium, Aspergillus, Penicillium)
Specific IgE blood tests
Allergy to Alternaria is particularly associated with severe asthma in children

Avoidance Strategies

Fix leaks and damp — mould cannot grow without moisture
Run bathroom and kitchen extractor fans; use a dehumidifier in damp rooms
Clean visible mould with appropriate antifungal products; wear a mask when cleaning
Avoid compost heaps, leaf piles, and damp basements — outdoor mould hotspots
Check and clean air conditioning units regularly — they can harbour mould
Keep indoor plants to a minimum; moist compost can support mould growth

Alternaria and severe asthma

Alternaria alternata is an outdoor mould with spore counts that peak in late summer and autumn. Sensitisation to Alternaria is one of the strongest risk factors for severe, life-threatening asthma attacks in children and young adults.

Patients with asthma who are Alternaria-sensitised should be particularly vigilant on warm, dry, windy days after rain — conditions that disperse spores widely.

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Medical disclaimer

This page is for educational purposes only. Allergy diagnosis and management must be carried out by a qualified allergist. Do not attempt to test yourself with suspected allergens. Always carry prescribed emergency medications and follow your written action plan.

Reviewed 2026-06-01 · Looms Medical Team