House Dust Mites are tiny spider-like 8-legged creatures called dermatophagoides pteronyssinus.  They do not bite and are invisible to the naked eye being only 0.3 mm in length  The adult mite lives about 6 weeks, lays 50 eggs and produce 20 faecal pellets per day, which contain the allergen Der P1 (a dermatophagoides digestive enzyme).  Der p 1 is the allergy-provoking particle produced by the House Dust Mite that triggers asthma and allergic rhinitis. This protein penetrates clothing, bedding, carpets and upholstery and can remain airborne for prolonged periods.  Mites require 70% humidity to survive as they extract water vapour from ambient air to live. The indoor temperature needs to be about 20deg C for them to survive as they are cold-blooded. They do not survive at high altitudes over 1500 metres, in “sterile” hospital environments or in very dry places.  House dust mites live on shed human skin flakes and fungal moulds growing on the dead skin flakes make them more edible.  Mites have adhesive suckers on their legs with which they cling to carpets and bedding.  Predator mites (Cheyletus) who in turn eat the common House dust Mites have less adhesive suckers and are preferentially vacuumed up, allowing allergy-provoking mites to proliferate.  Mites will colonize a new mattress within 3 months with up to 10 000 mites inhabiting an average mattress.

Can we get rid of this allergy-provoking scourge?  They are extremely difficult to completely eradicate from our bedroom environment. Chemicals that kill mites called acaricides may themselves trigger asthma but read more……….