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Encyclopedia > House dust mite
House dust mite
Dermatophagoides pteronyssinus
Dermatophagoides pteronyssinus
Conservation status
Secure
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Arachnida
Subclass: Acarina
Order: Acariformes
Family: Pyroglyphidae
Genus: Dermatophagoides
Species: D. pteronyssinus
Binomial name
Dermatophagoides pteronyssinus
Trouessart, 1897

The house dust mite (sometimes abbreviated by allergists to HDM), is a cosmopolitan guest in human habitation. Dust mites feed on organic detritus such as flakes of shed human skin and flourish in the stable environment of dwellings. In nature they are killed by micro-predators and by exposure to direct sun rays. Dust mites are the most common cause of asthma and allergic symptoms worldwide|May 2008. The enzymes they produce can be smelled most strongly in full vacuum cleaner bags. The European house dust mite (Dermatophagoides pteronyssinus) and the American house dust mite (Dermatophagoides farinae) are two different species, but are not necessarily confined to Europe or North America. House Dust Mite (Dermatophagoides pteronyssinus) File history Legend: (cur) = this is the current file, (del) = delete this old version, (rev) = revert to this old version. ... The conservation status of a species is an indicator of the likelihood of that species remaining extant either in the present day or the near future. ... Scientific classification redirects here. ... For other uses, see Animal (disambiguation). ... Subphyla and Classes Subphylum Trilobitomorpha Trilobita - Trilobites (extinct) Subphylum Chelicerata Arachnida - Spiders, Scorpions, etc. ... Orders Acarina Amblypygi Araneae Opiliones Palpigradi Pseudoscorpionida Ricinulei Schizomida Scorpiones Solifugae Uropygi The arachnids, Arachnida, are a class of invertebrate animals in the subphylum Chelicerata. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Suborders Acariformes Parasitiformes Opilioacariformes Acarina or acari is an order of arachnids that consists of mites and ticks. ... Latin name redirects here. ... Édouard Louis Trouessart (August 25, 1842 - June 30, 1927) was a French zoologist. ... An allergy or Type I hypersensitivity is an immune system malfunction whereby a persons body is hypersensitised to react immunologically to typically nonimmunogenic substances. ... A cosmopolitan distribution is a term applied to a biological category of living things meaning that this category can be found anywhere around the world. ... This article is about modern humans. ... Mites, along with ticks, belong to the subclass Acarina (also known as Acari) and the class Arachnida. ... For the trade organisation, see Federation Against Copyright Theft. ... Neuraminidase ribbon diagram An enzyme (in Greek en = in and zyme = blend) is a protein, or protein complex, that catalyzes a chemical reaction and also controls the 3D orientation of the catalyzed substrates. ... Regular canister vacuum cleaner for home use. ...

Contents

Size

It is possible to see a dust mite under a magnifying glass, when the subject is well lit and placed on a black background. A typical house dust mite measures 420 µm in length (almost 0.5 mm) and 250 to 320 µm in width. Both male and female adult house dust mites are globular in shape, creamy white and have a striated cuticle. A member of the class Arachnida, larval and post-larval stages of house dust mites have eight legs. Dust mites can be transported airborne by the minor air currents generated by normal household activities. External, internal, and depth micrometers A micrometer is a widely used device in mechanical engineering for precisely measuring thickness of blocks, outer and inner diameters of shafts and depths of slots. ... Eponychium is the anatomical term for the human cuticle In biology, the term cuticle or cuticula is given to to a variety of tough but flexible, non-mineral outer coverings of an organism, or part of an organism, that provide prtoection. ... A class is the rank in the scientific classification of organisms in biology below Phylum and above Order. ... For other uses, see Arachnid (disambiguation). ...


Life cycle

The average life cycle for a male dust mite is 20 to 30 days, while a mated female dust mite can live for 10 weeks, laying 60 to 100 eggs in the last 5 weeks of her life. In a 10 week life span, a dust mite will produce approximately 2000 fecal particles and an even larger number of partially digested enzyme-infested dust particles. [1]


A simple washing will remove most of the waste matter. Temperatures of over 60 degrees Celsius (140 degrees Fahrenheit) for a period of one hour, and freezing is usually fatal to dust mites;[1] a relative humidity less than 50 may also be fatal. Dust mites reproduce quickly enough that their effect on human health can be significant.


Habitat and food

The dust mite survives in all climates, except at high altitudes where reproduction is halted. If trying to control dust mites and other indoor pathogens for which water is a gating factor, it is relative humidity that is important. This is because water condenses out of air onto a surface only when the air at that surface contains more water than it can hold at that temperature. When warm, moist air contacts a cool surface, the air touching that surface may cool and give up some of its moisture to condense on the surface. When humidity is less than optimal, dust mites function more slowly, eventually become dormant and may die. Dust mites thrive in the environment provided by beds, kitchens and homes in general, where the sun's rays do not reach them. Mites remain in mattresses, carpets, furniture and bedding, since they can climb lower down through the fabric to avoid sun, vacuum cleaners, and other hazards, and climb higher up to the surface if necessary to get another skin cell to feed on, when humidity is high. Even in dry climates, dust mites survive and reproduce easily in bedding (especially in pillows) because of the humidity generated by the human body during several hours of breathing and perspiring.


Dust mites consume minute particles of organic matter. Some species of mites prefer to eat skin cells, a large component of household dust; others prefer flour dust. Dust mites have a rudimentary alimentary system (no stomach) and require most digestion to occur outside their body. For this reason they secrete enzymes and deposit the fungus Aspergillus repens on dust particles, to enable the fungus to pre-digest the organic matter with its enzymes. Dust mites eat the same particle several times, only partially digesting it each time. Between feedings dust mites leave particles to decompose further. Ultimately a fully digested particle, which a dust mite will not eat, is deemed by scientists to constitute fecal matter.[weasel words] On average, a person sheds about 1.5 grams of skin cells and flakes every day (approximately 0.3-0.45 kg per year), which is enough to feed roughly a million dust mites under ideal conditions.[verification needed]. Dust mites in bedding derive moisture from human breathing, perspiration, and saliva. Skin cells have most common organelles in them. ... Look up dust in Wiktionary, the free dictionary. ... The gastrointestinal or digestive tract, also referred to as the GI tract or the alimentary canal or the gut, is the system of organs within multicellular animals which takes in food, digests it to extract energy and nutrients, and expels the remaining waste. ... For the fictional character, see Fungus the Bogeyman. ... For other meanings of gram, see gram (disambiguation). ... Perspiration (also called sweating or sometimes transpiration) is the production and evaporation of a fluid, consisting primarily of water as well as a smaller amount of sodium chloride (the main constituent of table salt), that is excreted by the sweat glands in the skin of mammals. ... For the band, see Saliva (band). ...


Asthma and allergies

Main article: Asthma

Dust mites are one of the most common allergens that trigger asthma.


Some main signs of dust mite bites are itchiness, sneezing, inflamed/infected eczema, watering eyes, runny nose, (if asthma), lungs clogging up and hay fever.


References

  1. ^ "Hotter is better for removing allergens in laundry", American Thoracic Society, May 20, 2007. 

External links


  Results from FactBites:
 
dust mite, dust mite allergy, dust mite spray, dust mite allergies-allergens-house (1030 words)
A dust mite is a microscopic, eight-legged insect.
Dust mites are found on people, animals and on almost every surface in homes, including carpet, upholstered furniture, mattresses and box springs, sheets and blankets, pillows and stuffed animals.
Dust mites feed on pet dander and your family's health is more important than the habits of your pet.
House Dust Mites, HYG-2157-97 (1391 words)
Estimates are that dust mites may be a factor in 50 to 80 percent of asthmatics, as well as in countless cases of eczema, hay fever and other allergic ailments.
House dust mites, due to their very small size (250 to 300 microns in length) and translucent bodies, are not visible to the unaided eye.
Dust mite populations are highest in humid regions and lowest in areas of high altitude and/or dry climates.
  More results at FactBites »


 

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