Invisible to the naked eye but omnipresent in our daily lives, dust mites are these microscopic roommates that slip into our mattresses, on our skin and even… on our cheese! Often associated with allergies or itching, there is more to these arachnids than just their bad reputation. Their diversity is dizzying — over a million supposed species — and their almost universal presence. But who are they really? Friends, enemies or simple stowaways in our environment? Through a surprising true/false, I’m interested takes stock of these little invaders that we think we know… but who still have many secrets to reveal.
1/ Mites are insects
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Faux. Just like spiders and scorpions, mites belong to the arachnid family and have eight legs. Some 50,000 species have been listed but their diversity could exceed a million. Most are invisible to the naked eye and measure on average 0.7 millimeters, such as Paratarsotomus macropalpis (the fastest animal in the world relative to its size). But some species can reach 30 millimeters, like the chigger or tick. Yes, the plague of forest walkers and dogs is none other than a large mite!
2/ We find mites everywhere
TRUE. If these little creatures have managed to invade our homes (bedding, carpets, curtains, etc.), they have also invaded the entire planet: on land, in the seas and deserts, in cities, on plants and animals. Some live independently, others as parasites or in harmony with their host. The incredible variety of their ecological niches is explained in particular by their very ancient existence. The oldest mite fossils discovered date back to the Devonian, about 400 million years agomuch earlier than the dinosaurs!
3/ We have mites on our bodies
TRUE. Nobody likes to think about it but millions of little creatures roam the surface of our skin. Feeding on our sebum, tiny mites (about 0.3 millimeters long) of the species Demodex follicles et Demodex short live in our sebaceous glands and at the roots of our hair. They come out at night to breed. They are mainly found on our eyelashes, eyebrows and sides of the nose as well as on the breast areolas.. Their high prevalence among people suffering from rosacea and of rosacea led to them being accused of being the cause of these conditions, which is now being called into question.
4/ Mites bite us while we sleep
Faux. Unlike mosquitoes, bedbugs, fleas and some flies, dust mites that live inside our homes do not sting or bite. They are content to delight in our little dead skin, organic debris, mold and in fact act as shadow cleaners.
5/ Mites cause allergies
TRUE. Dust mites are the main cause of allergies in the home and can trigger irritations and reactions in humans: rhinitis, asthma and dermatitis. Their debris (shells, excrement, eggs) are in fact loaded with allergenic proteins. And since up to two million of these individuals are capable of living in a mattress, traces of their presence can quickly accumulate. It is estimated that after two years these pests represent 10% of the weight of a pillow! Likewise, so-called “storage” mites, lovers of humidity, can proliferate in food reserves. Farmers, farmers and bakers are particularly affected by respiratory allergies caused by these arachnids.
6/ We can get rid of mites
False but… we can limit its proliferation. If mattresses treated against these parasites have a short-term effectiveness and can prove irritating due to the products they contain, on the other hand, full anti-mite covers show real effectiveness and could reduce the presence of allergens by 60 to 98% according to a 2014 study from the School of Public Health and Tropical Medicine at Tulane University (United States). Likewise, washing sheets and pillows frequently at over 60°C and cleaning mattresses at least once a year helps contain their presence. Lovers of humidity and heat, mites die outright when humidity drops below 55%. For this reason, above 1,500 meters of altitude, domestic mites become rare. Unless you live in the mountains, ventilation and limiting heating is essential.
7/ Mites carry dangerous diseases
True and false. House dust mites do not transmit infectious diseases and are harmless outside of risks of allergies. This is not the case for all species. Ticks can thus transmit Lyme disease and certain encephalitis; chiggerswhose bites cause severe itching, are vectors of scrub typhusa disease particularly widespread in Southeast Asia.
8/ Mites are essential for the production of certain cheeses
TRUE. We generally recognize these products by their crust with a multitude of holes. These small cavities are caused by cirons, also called “flour mites“, white critters visible to the naked eye. Usually considered as pests of stored foodstuffs, they are used – under control – by producers of old mimolette, artison cheeses or from tomme ceronnée to promote aeration and gas exchanges necessary for the development of aromas and texture.
