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What are chiggers?
Chiggers are the juvenile form (larvae) of a certain type of mite of the family Trombiculidae. Mites are arachnids (like spiders and ticks).
Chiggers are tiny members of the arachnid family. Although they are extremely small in size, their bites pack a powerful punch. They’re so tiny that you probably won’t notice when they jump from that tall blade of grass onto your skin. You won’t feel it as they hitch a ride right into your home. When you eventually do feel them, however, they can make you itch like you’ve never itched before.
Chiggers are found throughout the world. They most commonly live in forests, grassy fields, gardens, parks, and in moist areas around lakes or rivers. Most of the larvae that cause chigger bites are found on plants that are relatively close to the ground surface, because they require a high level of humidity for survival.
What do chiggers look like
Chiggers are barely visible to the naked eye (their length is less than 1/150th of an inch). A magnifying glass may be needed to see them. They are red in color and may be best appreciated when clustered in groups on the skin. The juvenile forms have six legs, although the (harmless) adult mites have eight legs. Because of their red color, you might be able to spot the larvae when they cluster together. After they feast on human skin cells, they turn a yellowish color.
Only the larvae bite humans. They tend to choose warm, moist areas of the body. Chiggers have claws that help them grab onto skin. The chigger then attaches its mouth to the skin and injects saliva. The saliva contains an enzyme that breaks skin cells down to liquid form. Your body responds by hardening skin cells around the saliva, creating a tube (stylostome) through which the chigger sucks the dissolved skin cells. Chiggers can stay attached and feeding for several days before falling off.
The chigger mite is about 1/150th of an inch in length, meaning it is only barely visible to the naked eye. The juvenile forms, which bite humans, have six legs, while the adult forms have eight legs. Chigger mites are red in color, and the juvenile (biting) forms require a relatively humid environment, so they are most commonly located in vegetation that is near ground level. When human skin or clothing comes in contact with low-lying vegetation that hosts chiggers, the mites can infest the human and migrate on human skin in search of a feeding area.
Chiggers most commonly bite in areas of thinned skin such as wrinkles and folds. Therefore, chigger bites are commonly observed in the crotch and groin areas, in the armpits, and in the folds behind the knees. The ankles are also a common site for chigger bites. Other areas that are commonly bitten by chiggers are areas where the compression of clothing (such as belts) presents barriers to their migration.
A popular myth about chiggers is that they burrow into the skin and remain there, but this is incorrect. When the chigger bites, it inserts its feeding structures and mouth parts into the skin. They inject enzymes into the host skin that destroy the host tissue. The area then hardens, and a feeding tube, called a sylostome, develops at the bite area. Chiggers can feed on the skin for a few days through this structure if they are not disturbed.
Symptoms of chigger bites?
A chigger bite itself is not noticeable. After the chigger has begun to inject digestive enzymes into the skin (usually after about 1-3 hours), symptoms typically begin.
♦ Pronounced itching is the most common symptom. ♦ The area of the bite may be reddened, flat, or raised; sometimes it resembles a pustule or blister. ♦ The itch is due to the presence of the stylostome and usually is most intense within 1-2 days after the bite. ♦ The itching persists for several days, and complete resolution of the skin lesions can take up to two weeks.