Chiggers are tiny, six-legged wingless organisms (larvae) that grow up to become a type of mite. Chiggers are found in tall grass and weeds. Their bite causes severe itching.
Harvest mite; Red mite
Causes, incidence, and risk factors
Chiggers are found in certain outdoor areas, such as berry patches, tall grass and weeds, and woodland edges.
Chiggers bite humans around the waist, ankles, or in warm skin folds. Bites commonly occur in the summer and fall months.
The main symptoms are:
Itching usually occurs several hours after the chiggers attach to the skin. The bite is painless.
A skin rash may appear on the parts of the body that were exposed to the sun. It may stop where the underwear meets the legs. This is often a clue that the rash is due to chigger bites.
Signs and tests
A doctor can diagnose chiggers by examining the rash.
The goal of treatment is to stop the itching. Antihistamines and corticosteroid creams or lotions may be helpful.
Secondary infection may occur from scratching.
Calling your health care provider
Call for an appointment with your health care provider if the rash itches very badly, or if symptoms get worse or do not improve with treatment.
Avoid outdoor areas contaminated with chiggers, if known. Applying bug spray containing DEET to skin and clothing can help prevent chigger bites.
Diaz JH. Mites (including chiggers). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 296.
Elston DM. Arthropods and leeches. In: Goldman L, Schafer AI, eds. Cecil Medicine. 24th ed. Philadelphia, Pa: Saunders Elsevier; 2011:chap 367.
International Classification of Diseases, 9th Revision (ICD9)133.8
Review Date: 10/6/2012
Reviewed By: David C. Dugdale, III, MD, Professor of Medicine, Division of General Medicine, Department of Medicine, University of Washington School of Medicine; Jatin M. Vyas, MD, PhD, Assistant Professor in Medicine, Harvard Medical School; Assistant in Medicine, Division of Infectious Disease, Department of Medicine, Massachusetts General Hospital. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M. Health Solutions, Ebix, Inc.