Anti Dust Mite Materials
All TopSleep™ Mattresses are made with Anti Dust Mite Materials.
What are house dust mites?
Mites are arachnids, making them close relatives of spiders and scorpions. They belong to the subclass Acari, and house dust mites are part of the family Pyroglyphidae. There are several species, but the most common are Dermatophagoides pteronyssinus, the most prevalent species in Europe, and Dermatophagoides farinae, the most common in America. A smaller species, Euroglyphus maynei, is the second most abundant species in Europe.
What do they eat?
House dust mites feed on human skin scales which we shed all the time. Unfortunately for the mite, a newly-shed skin scale is not particularly desirable – it is too fatty and too dry for the mite to ingest. However, the skin that we shed often becomes infested with a fungus called Aspergillus repens which takes out the fat and adds water, thereby making the skin scale perfect for the dust mite’s needs.
Where do they live?
House dust mites, unlike many of their close relatives, do not have a hard outer covering. They have a thin, permeable skin, which makes them vulnerable to water loss. Hence, mites like to live in places of high humidity – ideally 75–80% relative humidity (RH). They also need to be in a location that will provide them with a constant supply of human skin. One of the most common places to find house dust mites is in the bed. We all shed approximately 1g of skin a week in our beds, and we spend up to eight hours a day there, producing about a pint of water in sweat, which causes the RH to remain at a high level.
House dust mites can also be found in carpets and upholstery. Both are sites that can accumulate skin scales if not cleaned often and thoroughly, and, like mattresses and pillows, they are changed infrequently, allowing dust and therefore mite populations to build up over many years.
Why are they a problem?
Throughout their lifetime (approximately 3 months), house dust mites produce around 2000 faecal pellets, each containing digestive enzymes to which some people are allergic. These small pellets are breathed in by humans, becoming lodged in the bronchi, which are the two branches of the respiratory tract between the trachea and the bronchioles. In allergic people, these pellets cause a local inflammation in the area of the bronchi where they have lodged. If a person is exposed to house dust mite faeces over a long period of time the inflammation becomes chronic i.e. persists for a long period of time, and becomes spread over a wide area. Because the once wide, smooth airway is now narrowed and uneven, the airflow through it becomes turbulent, causing wheezing and shortness of breath. In short, the house dust mite allergen plays a major part in the development of allergic asthma.
How does an asthmatic attack occur?
If, in a non-asthmatic person, something becomes lodged in one of the bronchi, the body’s natural response is to send the bronchus into spasm until the blockage is removed. For example: That is, if a piece of food, say, gets stuck in the throat, it is instinctive to try to cough it up and out. If, in the asthmatic as described above, an irritant causes the already inflamed bronchi to become more so, the airway becomes so constricted that the body thinks there is a blockage and tries to cough it out. However, since there is no blockage, the coughing continues and it becomes very difficult to breathe in – they experience an asthmatic attack. This, as all asthmatics know, is a very frightening experience both for the sufferer and for any onlooker. An asthmatic attack can be triggered by many different factors. Some are listed below:
- Pollen grains
- Pet dander
- Tobacco smoke
- Traffic fumes
- A cold or flu
- Vigorous exercise
- Cold air
- Strong emotion
It should be noted that the factors listed above are TRIGGERS of asthmatic attacks; they are NOT causes of asthma. The underlying cause of allergic asthma is thought to be the house dust mite allergen in 85% cases.
What can be done?
Asthma is a very debilitating disease, causing many deaths each year. Millions of pounds are spent every year on medicines such as bronchodilators, which open the airways to stop asthmatic attacks, and corticosteroids, which reduce the bronchial inflammation. However, neither of these treatments will cure asthma – they just alleviate the symptoms. If you suffer from mite-induced asthma, reducing the number of mites and level of mite allergen in the house can make an immeasurable improvement to your quality of life. Several simple measures can do this:
To reduce the number of mites in your home and bed:
- Wash or dry-clean pillows and bedclothes regularly, at a high temperature if possible
- If hot washing is not possible, 24 hours in the freezer will kill all the mites in a pillow prior to a cold wash
- Leave bedclothes turned back during the day
- Leave windows open where and when this is sensible to do so
The last two measures here will increase the ventilation and reduce the humidity around the bed and in the home generally. This makes the home less habitable for house dust mites. Also, increasing ventilation prevents a build-up of dust, etc. in the home, which may irritate the throat and provoke asthmatic attacks. Obviously, with the risk of burglary, many people are unable to leave windows open during the day, and unwilling to do so at night during the winter. An alternative is to invest in a ventilation unit with a heat exchanger. This will increase the air changes in a room without affecting the temperature, extract allergens from the room and prevent allergens from outside entering.
To reduce the level of mite faeces, and therefore allergen, in the home:
- Wash pillows and bedclothes regularly
- Vacuum mattresses, carpets, upholstery, etc. thoroughly
- Dispose of and replace, mattresses and pillows on regular basis
It is important that vacuuming be carried out with a good quality cleaner that does not pump the dust straight back out. This, as well as having little effect on the allergen levels in the home, can also provoke an asthmatic attack.
By reducing the allergen levels in the home (either directly or by removing the mites) , the inflammation of the bronchi slowly subsides, and the likelihood of an attack being provoked decreases. However, there may be no noticeable improvement in health for several months, so do not assume that the changes are ineffective because the asthma does not disappear overnight.