Grass mites are often popularly denounced as the culprits for certain itchy bites. They are completely innocent of the symptoms that often last for weeks and typically occur after spending time in nature. Who is actually behind it and how remedial action can be taken is finally clarified below.
What helps against grass mite bites?
Grass mite bites are actually bites from fall mite larvae that cause scarlet welts and severe itching. Lemon juice, onion, 70% cosmetic alcohol or anti-allergic ointments for relief and disinfection are recommended as first aid measures.
Grass mite in humans?
Itchy spots in the torso and intimate areas of the body are sometimes not correctly diagnosed right away. On the one hand, this is because the culprit is hiding behind a fellow animal. The fact that grass mites are often blamed is due to a common definitional misunderstanding. To set the record straight: Grass mites are usually irrelevant to humans.
The actual cause of the disease is the autumn mite, which also has a few other common names. These include, for example, autumn grass mite (particularly confusing), harvest mite, hay mite, grass louse, biting louse, ground louse or peach louse.
The clinical picture that humans show when they are infested with autumn mites is called harvest scabies. Why? Because it is a typical phenomenon of the harvest season and was probably an all too well-known, unpleasant side effect of the actually happy, richly gifted phase in late summer and autumn in earlier times in farming circles. Alternatively, harvest scabies is also called hay scabies, autumn bite or gooseberry disease.
Actually, animals, especially mammals such as mice, other rodents, dogs or cats, are primarily parasitized by the “grass mite”. Humans basically only serve as an alternative host for the pests - so to speak, when nothing better is available.
Excursus
Mites are spiders
By the way: Like all mites, autumn and grass mites are not insects, but arachnids. This can be easily recognized by the eight legs of the adult animals. But be careful: like insects, the larvae only have six legs! Incidentally, it is also the larvae that are important for animals and humans: because they are the ones that attack the skin and cause the itchy bites. Despite their tiny size, they can be seen with the naked eye.
Here is a picture so you can get an idea of the animals:
Grass mites are difficult to see with the naked eye
And here is a brief overview of how to distinguish between autumn mites and grass mites:
table:
| Autumn mite | Grass mite | |
|---|---|---|
| Zoological name | Neotrombicula autumnalis | Bryobio Gramineum |
| Alternative common names | Autumn grass mite, harvest mite, hay mite, grass louse, biting louse, ground louse, peach louse | None |
| Appearance | Larvae up to 0., 3 mm, oval, pale orange coloring; adults up to 2 mm large, wide dorsal shield, double eyes | Significantly smaller than autumn mites, larvae also have six legs, adults have eight legs |
| Relevance to humans | Parasitization in late summer/autumn with frequent contact with grass, severe itching symptoms | At most very occasional bites, they itch significantly less |
How can “grass mite bites” be recognized?
Let's take a closer look at this unsightly evil so that we can get to grips with it. Typical characteristics of autumn mite bites are as follows:
- several scarlet wheals occurring at the same time, sometimes single, larger ones, sometimes several small ones in a rash
- preferred in areas close to the torso, in the intimate area and in the inner crooks, preferably those with thin skin and under tight-fitting clothing. For example in the groin and lumbar area, under the armpits, in the back of the knees and in the crooks of the arms or even on the wrists and ankles
- often severe itching that can last up to 2 weeks
The characteristic places where harvest scabies manifests itself are the ideal attack points for the autumn mite larvae, because here they have little to pierce through the corneal layer and are offered a pleasantly humid, warm environment.
The hives are not stings, but bites. The arachnids do not have a stinger, but rather use their mouthparts to bite through the skin to access nutritious cell juices and lymph. The animals do not suck blood. In order to access their food, they secrete a salivary secretion when they bite, which dissolves some of the skin tissue. The defensive release of histamine that then occurs causes the itching.
How does the disease progress?
Attributing the itchy pustules to the autumn mites is not entirely trivial. This is also due to the length of time that passes before it breaks out. The itching only occurs about 24 hours after the bite, the pustule formation usually occurs a little later.
This is because the larva can only create a so-called “pool”, i.e. a channel to the cell sap and lymph, by repeatedly processing the skin with its mouthparts. In addition, the warmth of the bed promotes the formation of hives, which is why you can easily suspect fleas or bed bugs as the culprits. It is often not obvious to the layperson that the hay harvest or the picnic on the meadow last weekend could have caused the “stings” that occur later.
The duration of itching and pustule formation
It takes about 1-2 days for the hives to develop. But then for some people it really gets to the point and severe itching occurs. However, some people react much less violently to the bites, which is why they sometimes go undetected. The itching, if present, can subside after just 3-4 days, but can sometimes last up to 2 weeks.
Reaction varies depending on susceptibility
The level of reaction of the person bitten depends on the condition of the skin and general sensitivity. People with soft, thin skin are more susceptible to the parasites anyway. Anyone who is also prone to allergies also releases more histamine when infested and develops a more intense defense reaction.
Scratching makes the symptoms worse
Scratching can really cause the bite to become infected
How the person bitten behaves is also relevant to the course of the disease. Anyone who knows anything about bug stings and bites knows that scratching only makes things worse. Because 1. this distributes the injected foreign proteins and increases their effective range. And 2. intensive scratching can cause small wounds to form, which in turn can form a channel for infections such as inflammation and other secondary skin diseases.
General countermeasures
To relieve the - as we now know: foreseeable - itching, you can first use normal home remedies and preparations from the pharmacy, which also help with insect bites. Examples include:
- Hold a cut lemon on the affected areas to reduce inflammation and relieve irritation
- Treat with sliced onion
- Disinfect and cool with 70% cosmetic alcohol (€7.00 at Amazon), this will also kill any remaining mites
- Use anti-allergic, soothing ointments
- If necessary, use hydrocortisone preparations (prescription required in higher doses)
Tip
In addition, if possible, you should wash all clothing and bed linen that you have worn in the last few days (several times) to remove any mites that may still be living on you!
When are “grass mite bites” particularly dangerous? Indications and remedies
The skin of young children is more sensitive than that of adults and should be protected
As a rule, an infestation of autumn mites is not really critical. The larvae of the animals only feed on their host for a few days and then drop off in order to move on to the next stage of development with the food they have eaten. They then become nymphs and then adult mites, which then only feed on plants.
Lymphedema
The infestation can become problematic if secondary diseases occur due to intensive scratching and the resulting infections. Through small scratch wounds, bacteria such as streptococci can penetrate the lymphatic vessels and cause edema. These manifest themselves as severe swelling and should be treated medically - especially in people with weak immune systems.
Allergy sufferers
Those who are generally prone to allergies also develop a stronger defensive reaction to “grass mite stings” or autumn mite bites. The itching is stronger due to the larger amount of histamine released and blisters can form on the pustules.
Countermeasures:
Antihistamines can be helpful, especially for allergy sufferers. They alleviate the strong immune reaction and the associated itching symptoms and thereby also prevent superinfections.
Toddlers
The problem with small children is often that they are still completely naive and trusting about the world and can therefore easily catch mite bites when playing in the grass. It is also harder for them to resist the intuitive scratching to relieve the itch. This results in a higher risk of infection, which in turn is more dangerous for the juniors because of their still small body mass and less developed immune system.
Countermeasures:
Because children have difficulty having the rational discipline to resist itching, local itching relievers are initially useful: Home remedies in the form of 70% cosmetic alcohol, lemon juice or onion juice, which are dabbed at the areas, can bring relief. However, medical support is certainly advisable at the same time. As with allergy sufferers, antihistamines can reduce itching and the risk of infection through scratching.
“Grass mite bites” on pets
As already mentioned, mammals are much more affected by harvest scabies than humans. Mice are the most popular prey of autumn mite larvae, but dogs, cats and horses can also become victims.
The signs of an infestation are basically the same as ours: the animal suffers from discomfort and scratches, licks and shakes itself incessantly. And scratching can also lead to open, inflamed areas in four-legged friends. This can be particularly problematic with bites to the head and eyes.
Dogs
Dogs are also often bitten by grass mites
Many dogs love to dig in the ground with their paws and snout and follow their instincts. In late summer and autumn they offer the hatching autumn mite larvae ideal opportunities to spring up: their snouts, paws and ears are welcome guest houses for them during their time until nymph stage.
Cats
Free-roaming cats that like to roam through tall grass can also be affected by autumn mites. Basically the same indicators and treatment options apply here.
Remedy
If you notice the above behavioral signs in your dog, you should check him for mites. To do this, comb the fur against the grain in vulnerable areas (ears, paws) and look for the tiny, orange-red animals. They are small, but can be seen with the naked eye. In order to be able to discover them better (this is not easy with reddish fur), you can also spread a white pad under the combing station and observe whether orange-red dots accumulate there. Of course you should also look for pustules on your skin.
So-called repellents are recommended as a preventive measure. They are available in the form of sprays or powder and can be used in the autumn mite season between July and October.
Help
First of all, you should shower your four-legged friend thoroughly and also thoroughly clean his blankets, pillows and baskets. If your pet is suffering too much from itching, you can also use special, itch-relieving animal ointments.
As a rule, autumn mite infestations in pets do not really require treatment because the mite larvae fall off again after 3-4 days.
Frequently asked questions
What helps with inflammation caused by “grass mite bites”?
The bites of autumn mites can be really painfully itchy. Hats off to anyone who can control themselves and not scratch. However, most people will not be able to resist the acute relief. If you scratch too intensively, small injuries can quickly lead to inflammation, which can cause even more problems.
The best way to mitigate or prevent redness, pain and, above all, the threat of secondary infections is through disinfection. Cosmetic alcohol (70% from the pharmacy) or good old home remedies such as sliced lemon or onion halves are suitable for this. All of this also has a pleasantly cooling and therefore irritation-relieving effect. By the way, raw potatoes are also an option that should not be ignored. A compress with diluted vinegar can also help.
Is a grass mite infestation contagious?
An infestation of autumn mites is not contagious in the classic sense. Because it's not an infection.
Nevertheless, an infected person can theoretically “supply” another person with the bug. The autumn mite larvae usually bite the skin once and fall off again once they have satisfied their appetite. However, under certain circumstances it can also happen that individuals are stripped of their clothing or bed linen prematurely. If someone else comes into contact with the textiles, they can become a new victim for the mite larvae.
Are they grass mite or flea bites?
The grouped pustules caused by autumn mites are easily confused with flea bites. To find out who the culprit is, you can first carry out your own investigation:
Basically, there is a higher risk of flea infestation if you are a pet owner. If you suspect that your bites could also come from fleas, inspect your four-legged friend. If you notice fleas on him too, you'll have a lot of clarity.
Nevertheless, you should also consult a dermatologist. Here, based on a thorough anamnesis, a reliable diagnosis can be made and the appropriate therapy can be initiated.
