Causes of grass mite bites
Grass mites show in the last years again an increased occurrence in Europe. The exact causes are not quite clear. Some voices blame climate change for the advance of the grass mites.
Others, on the other hand, claim that the changed leisure behaviour of humans has become attractive for the grass mites. Increased gardening and long walks on meadows and fields provide food for the larvae. Finally grass mites find in our widths increased favorable habitat such as flat meadows and gardens, which additionally guarantees food.
There they live in colonies on grass stalks and wait for protein-rich food in the form of human lymph fluid. Hosts with a temperature of 30 to 40 °C are optimal. Thus, humans fall into the prey scheme of the young larvae. Sandals and short pants are almost inviting for the hungry larvae, which from there reach the skin. They especially like to settle in warm skin folds or sock edges and suck lymph and cell juices there.
Diagnosis of crop dross
The diagnosis of harvest scabies – this is the name given to the skin reaction caused by the stings of grass mites – is relatively easy to make. A few hours after a walk or gardening, at the latest one day later, itchy spot-like redness appears. Unlike mosquito bites, however, these are numerous, up to hundreds of bites, distributed side by side or grouped together.
Especially preferred spots like the edges of socks, the intimate area, the waistband or the armpits are very suspicious. The grass mite larvae like to stay there because of the heat and body moisture. In principle, the skin changes, purely according to their appearance, could also have other causes, but the temporal connection with gardening or walks in the field is – in combination with the symptoms – the decisive indication. Further examinations, such as laboratory tests, are not necessary.
Are grass mites contagious?
Grass mites are not contagious for other people. After the larvae have sucked their fill on humans, they usually fall off the skin again. It is of course possible that the mite larvae remain in clothing.
New bites while wearing the clothes are then possible. Another person who puts on these clothes can also be bitten in this way.Most of the time, however, the larvae are then found in underwear or socks – these are not necessarily clothes that are shared with fellow humans. The larvae are not transmitted via skin contact.
The survival of the larvae in their own four walls is also very unlikely, as they find their natural habitat in meadows and gardens. After feeding, mite larvae develop into adult mites, by the way. These then no longer feed on humans and do not live as parasites.
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