Chiggers – The Unknown Arachnid
Scientifically known as trombiculid mites, chiggers are actually young larvae members belonging to the arachnid family. They are also called as red bugs, berry bugs, harvest mites, and scrub-itch mites. These creatures are minuscule and are visible only under a magnifying glass. They have a reddish appearance and are as small as 1/50th of an inch. Despite their small size, their bites are intense and excessively itchy. The adult trombiculid mite is practically harmless. It is the juvenile larvae that latch onto skin and causes irritation.
These mites mostly inhabit damp grasslands and bushes. Chiggers are considered to be parasitic larvae that feed extensively on humans, quails, frogs, rabbits, and few insects too. They are found all across the globe, mainly in moist surroundings such as grassy fields, forests, lakes, and ponds. Trombiculid mites experience the usual growth stages – egg, larva, nymph, and adult. Out of these, only in the larval stage does the mite attack the human skin.
Once these parasitic larvae have finished feeding on the human skin, they drop down and progress to the nymph and adult stages. In these stages, the organism is no longer parasitic in nature. When temperatures fall below 16 deg Celsius, they turn inactive. Below 4 degrees, these mites cannot survive.
Understanding the chigger bite
Human beings come in contact with chiggers while walking along moist grassy areas and tall weeds. These creatures, usually occurring in clusters, latch onto human skin. At this stage, it is impossible to detect them and brush them off the skin. They walk along the human skin and then gather at areas where the skin is thin, such as ankle, crotch, and groin areas. Once they detect a favorable location, they pierce the skin and release digestive enzymes into this incision. These enzymes start digesting the human cells, which acts as the source of food for them. Chiggers feed on the destroyed tissues through a feeding tube called as a stylostome.
This stylosome, that destroys and dissolves tissues, also hardens the surrounding skin area. This usually takes around 1-2 hours after the parasitic mite has latched onto the skin. A typical chigger bite creates enzymatic changes along with physical damage to the skin. This triggers an allergic reaction and immune responses from the body. Since the skin becomes pierced and exposed, it becomes susceptible to secondary bacterial infections. The intense itching is due two factors – first, due to an allergic response to the chigger’s saliva, and second due to the stylosome. Until this stylosome is dissolved by the body’s lymphatic system, the itching continues. This may take few days to a couple of weeks.
The tell-tale signs of a chigger bite
Initially, a chigger bite is invisible to the naked eye. Once the chigger starts secreting enzymes through the stylosome, it starts showing visible signs:
- Persistent itching at the spot of bite.
- Reddish bump on the skin which might be raised or flat.
- A skin blister which resembles a pustule or a pimple.
- In case the individual has a severe allergic response to the bite, it may even cause hives to form.
- When the chigger drops from the skin, it leaves behind a reddish dot on the bite location. This is where the stylostome was present.
- Since chiggers usually live in clusters, their bites on human skin are also found in a similar manner.
- Chiggers usually cluster around areas where the clothing is tight. That’s why one will find chigger bites mostly around the waist, ankles, behind the knees, and the crotch.
- Chigger bites on male genital can cause serious swelling and itching along with intense pain during urination.
Diagnosis and treatment
There are no specific diagnostic tests in order to detect a chigger bite. A physician is able to detect a chigger parasitic attack just by observing the typical symptoms – reddish itchy bumps in clusters, found in the usual areas. The intense itching and hardening of skin due to the stylostome is also taken into consideration. The doctor will also try to inquire if the said individual was involved in any outdoor activity or had come in contact with marshy vegetation.
The treatment of these bites usually doesn’t require a medical intervention as they can be easily treated at home. The best remedy is to take a hot shower and use a medicated soap to clean the entire body. After this, apply over-the-counter antiseptic creams on the bites. It is advised not to scratch the bites since it could break the skin more and invite secondary bacterial infections.
To soothe the intense itching, any hydrocortisone lotion or calamine lotion can be used. Since the larvae cannot survive below 4 degree Celsius, applying ice on the bite marks may help in reducing the itching. Oral antihistamines such as Benadryl can be taken to counter the allergic reaction.
You should visit the doctor if the symptoms continue to persist even after the above-mentioned remedies have been implemented. Alternatively, if the affected individual develops fever and chills and/or the swelling (with pus) due to the bite is more than usual, he/she should consult the doctor. To treat secondary infections, the doctor may prescribe you antibiotics.
Chigger bites – How to remain itch-free
The following precautionary methods can help one steer clear from such parasitic mite infestations:
- After every outdoor activity, especially if done in grassy/marshy areas, wash your hands and feet with soap and water.
- Wash your outdoor clothes with detergent and hot water, if you suspect a chigger mite infestation.
- If you are visiting a chigger-infested zone, cover your whole body with protective clothing. Wear full-sleeved shirts, gloves, full-pants, and socks to avoid exposing any part of the skin to the mites.
- Use mosquito repellent sprays/ creams on your body and clothing. This helps get rid of chiggers too.
(The featured image is licensed by eric.ray under Creative Commons Attribution 2.0 Generic License)
- Chiggers bites are neither contagious nor they cause any health complications such as infections, even if their enzymes mix with the bloodstream.
- Contrary to popular myth, these larvae, unlike other mites, don’t burrow into the skin.
- The attack of a chigger is not like a bee stinging or a mosquito sucking the blood. They puncture the skin and feed on dissolved tissues.
- Scratching a chigger off the skin by hand or shower is helpful since a scratched off chigger seldom bites.
- Chiggers need shady and damp areas to thrive. Closely cropped lawns and marshy vegetations are their preferred habitat.
Dos and Don'ts
- If you are highly allergic to chigger bites, wear chemically pre-treated clothes.
- While using a bug-spray pay special heed to exposed areas such as ankles, waist, and palms.
- Use sprays with herbal ingredients such as lemongrass, jojoba, and geranium extracts.
- Use bleach, alcohol, or any such substance to suffocate the chigger since these mites don’t live under the skin surface.
- Forget to take a hot shower. If there are no provisions to take a shower, try dislodging the mites by brisk towel movements and crushing them.
- Forget to change your bedding, as it might contain traces of mites. Wash all bed covers, blankets, and mattresses in hot water.
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