Scabies
Basics
Description
- A contagious parasitic infection of the skin caused by the mite Sarcoptes scabiei, var. hominis
- Typically, a clinical diagnosis based on history and physical exam
- System(s) affected: skin/exocrine
Epidemiology
Incidence
- Predominant age: children, sexually active young adults, and the elderly
- Male children from lower income quartiles were more likely to visit the ED in a retrospective analysis of nationally representative National Emergency Department Sample for 2013 to 2015, whereas older male patients, insured by Medicare, from the highest income quartile in the Midwest/West were most likely to be admitted to the hospital.
Prevalence
Prevalence varies substantially worldwide but is more common in resource-poor settings.
- More prevalent in areas of overcrowding and in developing countries, particularly tropical climates
- Added to World Health Organization’s list of neglected tropical diseases in 2017
Etiology and Pathophysiology
- S. scabiei, var. hominis
- An obligate human parasite
- Primarily transmitted by prolonged human-to-human direct skin contact
- Infrequently transmitted via fomites (e.g., bedding, clothing, or furnishings)
- Female mite lays eggs in burrows in the stratum corneum and epidermis.
- Itching is caused by a delayed type IV hypersensitivity reaction to the mite saliva, eggs, or excrement.
Risk Factors
- Prolonged skin-to-skin contact (e.g., sexual, overcrowding, nosocomial infection)
- Poor nutritional status, poverty, and homelessness
- Hot, tropical climates
- Seasonal variation: Incidence may be higher in the winter than in the summer (due to overcrowding).
- Immunocompromised patients (drug-induced), those with leukemia, lymphoma, or those with congenital immune deficiencies, including those with HIV/AIDS, are at increased risk of developing severe (crusted/Norwegian) scabies (1).
General Prevention
Prevent outbreaks by prompt treatment and cleansing of fomites (see “General Measures”).
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Citation
Domino, Frank J., et al., editors. "Scabies." 5-Minute Clinical Consult, 33rd ed., Wolters Kluwer, 2025. Medicine Central, im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/116544/all/Scabies.
Scabies. In: Domino FJF, Baldor RAR, Golding JJ, et al, eds. 5-Minute Clinical Consult. Wolters Kluwer; 2025. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/116544/all/Scabies. Accessed November 8, 2024.
Scabies. (2025). In Domino, F. J., Baldor, R. A., Golding, J., & Stephens, M. B. (Eds.), 5-Minute Clinical Consult (33rd ed.). Wolters Kluwer. https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/116544/all/Scabies
Scabies [Internet]. In: Domino FJF, Baldor RAR, Golding JJ, Stephens MBM, editors. 5-Minute Clinical Consult. Wolters Kluwer; 2025. [cited 2024 November 08]. Available from: https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/116544/all/Scabies.
* Article titles in AMA citation format should be in sentence-case
TY - ELEC
T1 - Scabies
ID - 116544
ED - Domino,Frank J,
ED - Baldor,Robert A,
ED - Golding,Jeremy,
ED - Stephens,Mark B,
BT - 5-Minute Clinical Consult, Updating
UR - https://im.unboundmedicine.com/medicine/view/5-Minute-Clinical-Consult/116544/all/Scabies
PB - Wolters Kluwer
ET - 33
DB - Medicine Central
DP - Unbound Medicine
ER -