The air from heating systems is actually lethal for house dust mites. This is because they die when it becomes too dry, and the air from heating is dry. In fact, one would expect the symptoms of people with dust mite allergies to improve during the heating period.
But it’s quite the opposite. The stuffy nose, cough, red eyes and tiredness get even worse. Symptoms are particularly severe at night and in the morning. They are due to an immediate hypersensitivity reaction that occurs within a few minutes. These symptoms affect the seven per cent of all Germans who are allergic to dust mites.
In the dry air from the heating, many mites actually die off. At the same time, however, the dryness also causes their faecal matter to disintegrate – which is where the real problem lies. People who are allergic to house dust mites do not react to the mites themselves, but instead to their droppings (for example, the proteins Der p1 and Der p2). These particles then mix in with the house dust. The heating air stirs up the dust, and the allergens become airborne. Everyone in the home breathes in this mixture of dust and allergens. It is impossible to escape it entirely because dust mites are found in every household, no matter how clean. So what are the options?
What can be done to relieve a dust mite allergy?
The first step is to check with a specialist whether the problem is actually allergy-related. Many people are sensitised to the allergy-triggering substances from house dust mites, but they do not have an allergic reaction. In other words, they have antibodies against the allergenic substances in their blood. However, it does not lead to an overreaction of the immune system.
An allergy only occurs when symptoms are present: stuffy nose, coughing and redness of the mucous membranes. This only happens when the immune system has an extreme reaction to substances that are actually harmless.
What if I have a dust mite allergy?
A house dust mite allergy should be treated, since it is highly likely that the allergy will turn into asthma. One in every two people with an untreated dust mite allergy develops asthma.
The first line of the treatment is hypersensitisation, a therapy in which very small amounts of the allergen are administered at intervals of a few weeks. As a result, the immune system learns to tolerate the protein. The allergens are either injected under the skin (subcutaneous immunotherapy) or taken as tablets or drops (sublingual immunotherapy).
More information on treatment can be found on the ECARF website.
Another important measure is to reduce dust and dust mites in the environment. To achieve this:
- Air out rooms well and keep them dry.
- Dust catchers (such as open bookshelves, lampshades, clutter) should be eliminated from the living space.
- Carpets should be vacuumed regularly (several times a week) surfaces wiped down with a damp cloth.
- It is recommended to use vacuum cleaners that measurably and safely reduce the indoor allergen load when used daily and keep the allergens inside the appliance. Vacuum cleaners do not completely remove dust mites from furniture. The suction of the devices is not strong enough to remove the mites from all layers
- A particulate filter in the vacuum cleaner is recommended, otherwise allergens can be disperse back into the room while vacuuming. HEPA (high efficiency particulate air) filters are a good choice. These filters hold particles as small as 0.1 micrometres (0.0001 millimetres) – and therefore also dust mites and mite allergens. However, you should not wash the filters because they will lose their effectiveness.
- Use special mite-proof covers for beds (encasings). They should also have good air and water vapour permeability.
- Air out bedding regularly and wash it at over 55 degrees; this temperature kills the mites.
Sources
Dtsch Arztebl 2016; 113(24):[34] (In German)
Fernandez-Caldas E et al. Mites and allergy.
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Miller JD. The Role of Dust Mites in Allergy.
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Pfaar O et al. Guideline on allergen-specific immunotherapy in gene-mediated allergic diseases.
Allergo J Int 2014;23:8. 282–319
Zuberbier T. Dust Mite Allergy. ECARF Patient website