House Dust Mite Allergy in Children

House dust mites are tiny (microscopic) organisms (related to spiders) that live in large numbers in the home. They thrive on dead skin and live in bedding, carpets and fabrics (like curtains). As they die, they become airborne - they are then present in house dust.

If you are not allergic to house dust mite, they cause you no harm.

What is House Dust Mite Allergy?

It occurs in some susceptible individuals, often those with an atopic (allergic) tendency. These people get symptoms when they are exposed to house dust mite allergen.

The protein from the house dust mite gets into the air as the mite decays and the protein can set up an IgE mediated allergic reaction - so the body recognizes the mite protein as abnormal and makes an antibody against it, and when the antibody and the protein join, chemicals (including histamine) are released causing symptoms.

What are the Symptoms of House Dust Mite Allergy?

The symptoms include:

• worsening eczema
• asthma
• hayfever - itchy eyes, runny nose, sneezing

How do you test to see if you are allergic to house dust mite?

Skin prick tests will show allergy to house dust mite - the larger the test, the more likely you will get symptoms when exposed to the mite (so to house dust).

What is the Treatment of House Dust Mite Allergy?

• The best treatment is Prevention of exposure to the house dust mite.
• If your child gets asthma or eczema with house dust mite, treatment of these conditions is important - see your doctor
• Some centers offer desensitization treatment for house dust mite

How Do you Prevent House Dust Mite Exposure?

The following measures can be tried. The more severe the reaction, the more measures you could try and implement:

• dust-proof mattress cover
• synthetic bed linen rather than wool blankets or down duvets
• synthetic pillows rather than feathers
• vacuum regularly
• wash bed linen regularly
• avoid fluffy toys - if your child must have a teddybear, buy one you can wash. Alternatively, put the toy in the freezer overnight about once a month
• wet-dust high bedroom furniture (dry dusting will only spread the dust in the air)
• avoid clutter - it only collects dust
• consider a dehumidifier or air conditioner if you live in a very humid area
• if feasible, consider removing carpets for an alternative flooring

A review of the literature has not shown any research evidence that supports measures to reduce house dust mites in reducing symptoms of asthma.

The US and UK guidelines give slightly different advice based on the research evidence. The UK advice is not to undertake any measures to reduce house dust mites to reduce asthma symptoms, while the US advice is to try reducing house dust mites.

I would advise against spending too much money on any measures to reduce house dust mites, particularly to reduce asthma symptoms, but some of the measures, like reducing clutter and wet dusting, make sense and don't cost much, so I would advise you do those. Putting the teddy bear in the freezer once a month to reduce mites, especially if your child usually sleeps with the teddy, is easy to do and will do no harm, so I would advise that. I wouldn't advise removing the carpet if you have it, however.