The “house dust” is the main source of allergens inside homes and buildings, it contains a complex mixture of materials of different origin and composition: fibers, hair, skin debris of people, skin particles of animals, insects, rest of indoor plants, fungal spores, bacteria, viruses, pollen and especially mites.
Currently in industrialized countries, most people can spend up to 95% of their time in closed establishments, spending very little time outdoors; This change in habits has triggered changes in the frequency of many allergic diseases.
By staying for a long time in these closed environments, we breathe air rich in potentially allergenic substances, which facilitates the appearance of allergy to dust.
Symptoms of dust allergy.
The main symptoms of a dust allergy are the following: watery or itchy eyes, cough, symptoms of allergic rhinitis predominantly in the evening, runny and stuffy nose, consecutive sneezing, allergic skin reactions such as atopic dermatitis, swollen skin or reddened throughout the year.
Usually, the discomfort is exacerbated at night and when getting up in the morning because the mattress is one of the main reservoirs for mites.
If the severity of the allergy predisposes to the appearance of episodes of bronchial asthma, there will be shortness of breath, chest pain or a feeling of tightness in the chest, difficulty falling asleep due to coughing or dyspnea, episodes of coughing and audible wheezing on exhaling. (wheezing) that worsens with the development of associated respiratory infections.
The symptoms are characterized by subsiding as the house is abandoned, and they are present throughout the year, although they usually decrease in winter, they become more pronounced in autumn and spring due to the fact that humidity and temperature promote the growth of mites. Some researchers have found that mites can worsen the observed symptoms of atopic dermatitis.
One of the most serious manifestations of a mite allergy is anaphylactic shock. This can occur by ingesting food contaminated with mites in atopic individuals, these can be: wheat flour, corn, rice, ham, chorizo, salami, pizza, biscuits, oats, breaded foods.
Fortunately, it is not something that happens often. Affected individuals manifest severe and lethal allergy symptoms such as dyspnea, angioedema, and bronchospasm.
Causes of dust allergy.
An allergy to dust mites is called “house dust allergy”. Some people suffer from an atypical hypersensitivity to a certain allergen, which in this case would be to mites.
It is an inadequate regulation of the body caused by an exaggerated defense reaction of the immune system to certain substances called allergens. It should be noted that these allergens do not affect the rest of the people who do not have this atopic condition.
What are mites?
Mites are a subclass of arachnid microorganisms, measuring approximately 0.3 millimeters in length and feeding on particles in house dust.
They can be found in objects that accumulate dust such as carpets, blankets, duvets, mattresses, pillows, stuffed animals, books, heavy curtains, upholstered furniture, cushions, they can accumulate in the air conditioner filter so it is advisable to clean them periodically.
There are almost 50,000 described species of mites and between 100,000 and 500,000 species that have not yet been classified. It is estimated that only 25 of more than 40,000 species of mites found are associated with allergic diseases in humans.
The mites most frequently involved in allergic processes belong to the Astigmatic order, in which only 3 super families are responsible for causing atopy problems:
- Pyroglyphoidae: to this family belong the Dermatophagoides (D.) pteronyssinus, D. farinae and Euroglyphus maynei, inducers of the majority of allergic sensitizations in Europe and the United States.
- Acaroidae: Acarus siro and Tyrophagus putrescentiae are the responsible species within this family.
- Glycyphagodae: Blomia tropicalis and Lepidoglyphus destructor are increasingly being observed as responsible for allergic conditions.
It is the fecal matter of the mites that causes the allergy; This material is suspended in the air; the individual breathes them and triggers the allergy. They prefer dark and damp places. They decrease or disappear with altitude and are not present in the exterior dust.
They are found in all houses, even the most hygienic and can live between two and three months, they reproduce very quickly if the favorable conditions of temperature (25-35ºC) and humidity (50-75%) are conducive to their growth.