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Dust mites are found wherever dust accumulates in the house and are estimated to number in the millions to hundreds of millions. They thrive in the warm, humid environment of homes, especially in bedding. Particular caution is needed when switching from summer to winter bedding.
Additionally, dust mites are prone to breed in unused or unwashed bedding, making it crucial to keep bedding clean. This article introduces the dangers of dust mites lurking in bedding and methods to control them.
Conditions and locations where dust mites breed
While dust mites have a relatively short lifespan of about two months, their reproductive capacity is very high. They can lay one, or sometimes more than two eggs per day, and are said to lay about 100 eggs in their lifetime. ※1
Here we introduce the conditions and locations where dust mites tend to breed.
Conditions for breeding
Dust mites thrive in hot and humid environments. Specifically, they are said to prefer temperatures around 25°C and relative humidity around 75%, and they feed on dust and dirt to reproduce.
Places where they tend to breed
In general, places in a home where dust mites tend to breed are fabric products such as bedding, carpets, and sofas, as well as tatami mats. Among these, bedding is said to be the place where dust mites are most abundant, as it easily becomes humid due to night sweats and accumulates human dander and dead skin cells, which serve as food for mites.
Dust mites lurking in bedding are difficult to eliminate with just sun-drying or vacuuming, so if not properly maintained, bedding can quickly become a dust mite habitat.
Types of dust mites that breed in bedding
There are said to be as many as 500,000 species of mites, but the three types that tend to breed in bedding are house dust mites (Dermatophagoides), predatory mites (Cheyletus), and ticks (Ixodidae). House dust mites account for 70-80% of mites found in homes, while ticks and predatory mites are said to be less numerous.
House dust mites are typical household mites. They do not bite humans but cause health problems indirectly as allergens. Ticks are large mites visible to the naked eye. Like house dust mites, they do not bite humans, but they are said to have a high risk of causing infectious diseases.
On the other hand, predatory mites bite humans and cause direct health problems. The skin on exposed areas of the body, especially those not covered by clothing, is particularly susceptible to bites, and the itching can last for about 7 days immediately after being bitten.
It should be noted that there are few species of mites that bite humans, primarily including predatory mites, house mites, bird mites, and rodent mites.
What happens if dust mites breed in your futon?
If dust mites breed in your futon, it can lead to health problems, such as direct bites, allergies, or infections.
Dust mite carcasses and feces, when dry, crumble into fine dust and can cause allergic diseases such as rhinitis, asthma, atopic dermatitis, and allergic conjunctivitis. These symptoms can also contribute to a decline in sleep quality.
Mold can cause allergies
The hot and humid environment that is ideal for dust mite reproduction is also similar to the conditions for mold growth, so caution against mold is necessary. Inhaling mold that has taken root in bedding can cause conditions such as bronchial asthma, atopic dermatitis, allergic rhinitis, and hives. Furthermore, if mold is left untreated, dust mites are also more likely to breed as they feed on mold, so be careful.
Even if mold is not visible on the surface of the futon, it may be growing inside the futon, so regular maintenance is necessary to prevent moisture from accumulating.
Periods to watch out for allergies caused by mites and mold
In Japan, dust mites and mold are said to increase during the hot and humid months of June to August. During this period, house dust mites tend to breed in large numbers, and the predatory mites that feed on them also increase.
However, the "time when mites increase" and the "time when mite-related health problems occur" are not the same. Symptoms such as dust mite allergies and mite bites often occur in autumn.
The causes of dust mite allergies are dust mite carcasses, shed skins, and feces. Therefore, nasal symptoms such as runny nose and stuffy nose, and conditions such as asthma and atopic dermatitis, peak around October, when large amounts of dust mite carcasses, shed skins, and feces from the massive reproduction during the rainy season accumulate indoors.
Also, predatory mites, which cause mite bites, breed by feeding on the house dust mites that increase from June to August. Therefore, mite bite symptoms also become more common in autumn.
What to do if you are bitten by dust mites
If you are bitten by dust mites, rinse the affected area with running water and apply an insect bite ointment. At this time, avoid scratching the affected area as it can damage the skin or intensify the itching due to irritation.
When bitten by a dust mite, redness and itching appear 1 to 2 days later, but the severity of the inflammation varies from person to person, so if it is severe, consult a dermatologist.
What happens if you don't wash your futon?
Sleep accounts for one-third of our lives. Therefore, futons accumulate a lot of dirt, including human sweat, sebum, dander, dead skin cells, food crumbs, dust mites, dust mite carcasses and feces, dust, pollen, mold, bacteria, and pet hair. However, because the dirt is not easily visible, it's easy to forget the obvious truth that "unwashed futons are dirty."
Also, while there are almost no dust mites in unused futons, if you continue to use them without washing, sweat and dirt will soak into and accumulate in the futon's batting, which will then serve as food for dust mites to breed. Especially when storing futons for a long period, make sure to wash not only the futon cover but also the batting before storing them.
How to tell if there are dust mites in your futon
You can check for dust mite infestation in your futon either visually or with a test kit.
Visually check for dust mite carcasses
Dust mites are extremely small, about 0.2mm to 1.0mm in size, and generally invisible to the naked eye. However, if they have bred in large numbers, their carcasses can be observed visually.
For example, if white powder-like particles are scattered on the futon, or if a lot of white powder accumulates when you vacuum, it's highly likely that the "white powder" consists of dust mite carcasses.
Using a test kit
You can also use a dedicated test kit to check for dust mites.
However, there are several types of test kits, and the methods of confirmation vary depending on the kit, such as those that allow you to visually check for dust mites with an included magnifying glass, or those that detect dust mite allergens to confirm their presence.
Washing is the best way to prevent dust mite bites in bedding.
Thoroughly washing a futon (soaking it in water and washing it clean, including the batting) not only removes dust mites and their feces but also effectively eliminates dirt such as dander, dead skin cells, and mold, which are food sources for dust mites, thereby suppressing their proliferation. Furthermore, a futon that has been cleaned is less prone to dust mite breeding.
However, if left unmaintained for six months, dirt will accumulate and dust mites will increase again. Therefore, for those who want to take dust mite countermeasures, purchasing a futon that can be fully washed is recommended. Wash your futon thoroughly once every six months or once a year to remove dirt from the batting and dust mite allergens.
Futons should be professionally cleaned!
For futons made of materials that cannot be machine washed or those that are bulky and difficult to wash in a home washing machine, professional cleaning is the safest option.
However, the average cost of cleaning is around 10,000 yen, which is somewhat expensive, and bringing the futon to the cleaning store itself can be a hassle. Furthermore, most of the dirt on futons that serves as food for dust mites is water-soluble, so water washing is more effective than dry cleaning, but it is also true that many types of futons cannot be water-washed.
To remove dirt and dust mite allergens, the only solutions are to wash the futon with water or replace it with a new one. If you find it bothersome to send your futon for cleaning regularly, or if your current futon cannot be water-washed, it might be a good idea to reconsider your bedding.
Sun-drying and futon beaters are ineffective
"Sun-drying" and "futon beating," often associated with dust mite control, are not very effective.
Dust mites are vulnerable to heat, and can be killed by exposing them to 50 degrees Celsius for 30 minutes, but in the case of sun-drying, the mites will simply escape to areas not exposed to direct sunlight.
Also, futon beating is not recommended as it can pulverize dust mite carcasses and feces, potentially scattering them on the surface and exacerbating allergy symptoms.
Pay attention to bedding choices to avoid dust mite bites
To suppress dust mite breeding, washing and keeping bedding clean is the most effective method. For those who use futons that cannot be washed completely or find it difficult to send their futons for cleaning, consider choosing futons or pillows that can be washed completely.
Take dust mite measures with washable bedding! Introducing recommended items
At Brain Sleep, we develop various bedding products to meet our customers' sleep needs and concerns. Our Brain Sleep pillows, comforters, and mattresses are designed to be fully washable, making them inhospitable to dust mites and always clean. Here, we introduce the features and highlights of our recommended items.
【Reference】 ※1
Millions to hundreds of millions of mites in one house - Expert supervised! A hazard map of "dangerous places" for mites revealed!
