Limpeza para alérgicos a poeira e ácaros — o que funciona (com fontes)

Dust mite allergies: cleaning matters more than medication

For people with diagnosed allergy to house-dust mites (approximately 10-15% of the Swiss population per aha! Allergy Centre), the quality of home cleaning affects symptoms as much as — if not more than — any drug therapy.

What dust mites are (and why they bother us)

House dust mites (Dermatophagoides pteronyssinus and farinae) are microscopic arachnids (300-400 micron) invisible to the naked eye. They live in mattresses, pillows, sofas, carpets, soft toys. They feed on the skin flakes we shed daily (1.5 g per day per person — enough to feed 1 million mites).

What bothers us isn't the mites themselves but their droppings and shed bodies — allergenic proteins (Der p1 and Der p2) that suspend in the air and trigger:

• Rhinitis (runny nose, sneezing, itching)
• Asthma (night cough, laboured breathing on waking)
• Atopic eczema
• Allergic conjunctivitis

Diagnosis confirmed by skin-prick test or blood test (specific IgE) prescribed by an allergist.

Integrated strategy — the 5 points that actually work

1. Weekly 60°C laundry

The point that makes the biggest difference. Mites die from dehydration and heat only above 60°C. Below that, they survive the cycle.

• Sheets, pillowcases, duvet covers: every week at 60°C
• Blankets and bedspreads: every 2-3 weeks at 60°C (if the label allows)
• Full drying immediately after washing (residual humidity = rapid recolonisation)

2. Anti-mite mattress and pillow covers

Oeko-Tex-certified covers with tightly-woven fabric (max 10 micron) create a physical barrier between sleeper and mattress.

• Cost: CHF 60-150 per set (mattress cover + 2 pillow covers)
• Lifespan: 5-7 years with standard maintenance
• Wash: every 2-3 months at 60°C

Brands referenced by aha! Allergy Centre: Allergosan, Sanas, Mepro Care.

3. HEPA vacuum

A "regular" vacuum without HEPA filter projects the finest particles (0.3-2 micron) back into the air — exactly the allergenic ones. A vacuum with HEPA H13 or higher captures 99.95% of those particles.

• Full vacuuming 2-3 times a week
• Particular attention: bed area, under the bed, sofa, carpets
• HEPA filters: clean monthly, replace every 6-12 months

Reference brands: Miele (standard HEPA filters), Dyson (cyclone + HEPA), Bosch BGS5 (HEPA H13).

4. Vacuumed mattress and baking soda

Mattresses can't be washed at 60°C, but a monthly procedure with baking soda is effective:

5. Indoor humidity below 55%

Dust mites need >55% humidity to reproduce. Below 50% the population drops significantly.

• Summer (June-August): dehumidifier mandatory in Switzerland (outdoor humidity often 60-80%). Cost: CHF 150-300 for a domestic model.
• Winter: heating naturally dries the air; often the opposite problem (too dry for mucous membranes). Never below 30%.
• Bathroom and kitchen: active ventilation (hood, extractor fan), open windows 5-10 min after shower/cooking.

Habits to adopt everywhere

• Air for 10-15 minutes every morning (BAG: essential air exchange)
• Carpets, faux-fur throws near the bed = NO
• Soft toys in the bedroom: max 2-3 washable, weekly washing, or freezer for 24 h every 2 weeks
• Heavy curtains: at least semi-annual washing, ideally replaced with light curtains or blinds (easier to dust)
• No smoking indoors: passive smoke worsens respiratory allergies (BAG, WHO)

When DIY isn't enough

What does NOT work (even if marketed as a "solution")

When to see a doctor

The following symptoms warrant medical consultation (family doctor or allergist):

• Persistent cough >3 weeks, especially at night
• Laboured breathing on waking
• Chronic rhinitis with morning peak
• Diffuse or recurring eczema
• Frequent allergic conjunctivitis

Rigorous cleaning is an essential component but doesn't replace diagnosis and pharmacological therapy where needed.