How to reduce the level of dust mites in your home

This leaflet is designed for people who have been diagnosed as being allergic to house dust mite. The measures described below should only be used if a diagnosis of an allergy to house dust mite has been made. This leaflet is for use in conjunction with advice from the Allergy Clinic and will usually be advised in addition to medical treatment.

Some allergies are caused or worsened by house dust mite. They can cause rhinitis (runny nose, eyes), asthma or eczema. If you are allergic to house dust mites, reducing the levels may help reduce symptoms.

What is house dust mite?

It is a very small and invisible creature, living in everyone's home, despite normal cleaning. They do not live on humans but feed off the dead skin cells that we shed. Allergies develop to the house dust mite droppings which can persist after house dust mites have died.

Where does it live?

House dust mites are found in all homes but prefer warm, humid conditions. They are found in mattresses and bedding but also in carpets, upholstery, chairs, curtains and clothing.

How can I reduce the number of mites in my house?

Measures to avoid house dust mite will lower but not completely remove house dust mite allergens. To lower the levels of mites sufficiently to reduce symptoms you should carry out the measures stated below.as thoroughly and as often as possible, concentrating especially on the bedroom, where dust mite levels are highest. Doing one or two measures inconsistently is unlikely to make a difference.

General tips

Vacuum at least once a week (ideally not to be done by the person allergic to house dust mite).

Damp dust the room at least once a week.

If you have the allergy and have to do the vacuuming, anti-allergy vacuum cleaners with HEPA filter which do not blow out dust may be helpful.

Declutter

Use barrier bedding covers (details below)

Avoid heavy curtains. Use lightweight washable curtains or blinds that can be easily washed and cleaned.

Reduce humidity by increasing ventilation e.g. opening windows, using extractor fans in bathrooms and kitchens. If necessary, use a dehumidifier to keep indoor humidity under 50% (but over 30%)

For those with a severe allergy, consider having vinyl or wood floors instead of fitted carpets in your home, especially in the bedroom.

Bedroom

Barrier mattress bedding covers

This is the single most effective measure but is not enough to help on its own. They are made of special fabrics which do not let house dust mites through. They are available as mattress covers, duvet covers and pillow cases and go under your normal bed covers. If a mattress cover is used there is no need to vacuum the mattress. Covers should be breathable, to allow water/body moisture to pass through them, and should completely enclose the item. Buy products that have been tested to show they prevent the escape of the house dust mite allergen.

A clean bed

• Wash all bedding that is not encased in allergy covers on a 60º Cycle including pillows, quilts, blankets, duvets (try to select materials which allow this). If a hot wash is not possible, these items can be dry-cleaned. A cooler wash will only partly kill the mites, but is better than nothing.
• If you do not have mattress covers vacuum the mattress once a week. Acaricides sprays are not recommended, as they are of limited help and may be an irritant and need to be avoided by children and pets..
• Please note: ideally do not do the vacuuming if you have an allergy to dust mites. You should stay out of the bedroom while the bed is being stripped, staying out for at least half an hour after the bed is remade.
• An alternative to washing pillows is to freeze them. Place in the deep freeze for 12 hours every month. This kills the house dust mite.
• Padded bed heads should be removed; the house dust mite will live in them.

Children’s bedrooms

If they have bunk beds, the child with the allergy should be on the top bed. Soft toys kept on the bed will contain house dust mite. Keep these to a minimum. Wash them in a hot wash as with bedding but if not possible freeze them for at least 12 hours once a month. You do not need to deprive a child of a favourite night time toy.

Other rooms

Thorough vacuuming (carpets, sofas, upholstered chairs etc) and damp dusting at least once a week.