What are house dust mites? Tips for allergy sufferers
An allergy to house dust mites is the second most common allergy in Germany. But what are house dust mites and what exactly triggers an allergy? Here we have collected the most important information.
What do house dust mites look like?
Dust mites are microscopic arachnids. They are between 0.1 and 0.5 millimeters small, with the females being significantly larger than the males. The body of the light-shy house dust mite is white and covered with hair-like bristles.
What do house dust mites feed on?
Dust mites feed on human skin flakes. This is also indicated by their scientific name Dermatophagoides , which means something like “skin eater”. A person loses about one to two grams of dead skin every day. Even this small amount is enough to feed about 1.5 million mites. Older skin flakes are preferred by the mites because they usually contain more moisture than freshly fallen skin.
How long do dust mites live?
The average lifespan of dust mites is between 30 and 100 days. Depending on the temperature and humidity, the lifetime can vary greatly. The mites find optimal conditions at 25 to 30°C and a humidity of between 65 and 80 percent. If such conditions are given, they also multiply particularly strongly. The main propagation time is therefore in the warm summer months from May to October.
Sexually mature females lay up to 300 eggs during their lifetime. Larvae hatch from these eggs, which develop into sexually mature house dust mites in two stages within about four weeks. In the larval stage, the animals are particularly resistant to environmental influences.
Where do house dust mites live?
Because dust mites feed on human dander, they prefer to live in places where it gathers. A warm, humid climate is also an advantage. The front runners are beds, where the small arachnids settle in roughly equal parts in the duvet and the mattress. But also upholstered furniture often has a high population of animals; Carpets, on the other hand, are less affected. Dust mites usually cannot survive outdoors.
Why do allergy sufferers react to house dust mites?
People with a house dust allergy do not actually react to the house dust mites themselves, as many people think. These are harmless to humans and cannot transmit any diseases. Allergy triggers are the proteins contained in the faeces of the arachnids.
The mites produce around 20 droppings per day, leaving around 200 times their own body weight in excrement over the course of their short lifespan. When the feces dry out, they break down into tiny particles and combine with house dust. If this is whirled up, it enters the respiratory tract via the air and thus triggers allergic reactions.