Definition of Chiggers
Chiggers: The larvae of one type of mites, of the family
Trombiculidae. The larvae, or juvenile forms, feed on vertebrates such as
humans, while the adult mites feed on soil. Chigger bites produce a red welt
accompanied by an intense and unrelenting itch. Chiggers are so tiny that they
can barely be seen with the naked eye. However, when they are present in a
group, they may be noticed on the skin due to their red color. When chiggers
bite humans, they inject a digestive enzyme into the host
skin that destroys tissue. It is this tissue, and not blood, that serves as food
for the chiggers. Chiggers have delicate mouth parts that typically can enter human skin only at
areas where the skin has folds or wrinkles. Most chigger bites occur around the
ankles, the back of the knees, the crotch, under the belt line and in the
armpits. The chigger bite itself goes unnoticed, and the itching may last for
days to weeks.
Picture of Chigger Eggs, Larvae, Nymph, and Adult

Last Editorial Review: 6/3/2009
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