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FACT SHEET: Scabies (also known as “itch mite rash”, “sarcoptic itch”, and “sarcoptic acariasis”, and historically as “seven-year itch”; caused by the human parasitic itch mite Sarcoptes scabei, var. hominis)

Date of Publication: August 7, 2014
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Is the initiation of non-invasive dental hygiene procedures* contra-indicated?

  • No.

Is medical consult advised? 

  • Yes. While a medical consult for oral health reasons is not required, a referral to a primary care provider (e.g., physician or nurse practitioner) is appropriate for definitive diagnosis1 and treatment2. In addition to the infested person, treatment is also recommended for household members, sexual contacts, and other persons who have had prolonged skin-to-skin contact with an infested person. In the case of crusted scabies3, treatment is recommended even with brief skin-to-skin contact.

 

Is the initiation of invasive dental hygiene procedures contra-indicated?**

  • No.

Is medical consult advised? 

  • Yes; see above.

Is medical clearance required? 

  • No.

Is antibiotic prophylaxis required? 

  • No.

Is postponing treatment advised?

  • Yes, until after patient/client has been successfully treated, because some dental hygiene procedures may involve being in close contact.

Oral management implications

  • Mode of transmission of parasites occurs most commonly via prolonged direct contact with infested human skin or during sexual contact.4 Less frequently, transfer from clothes, towels, and bedding may occur, but only if they have been contaminated by infested persons within 48 to 72 hours beforehand.5 Mites can burrow below the skin surface in fewer than 3 minutes. Typically, fewer than 10 to 15 mites are present on the entire body of an infested person who is otherwise healthy. However, people with the uncommon form of hyperinfestation known as crusted scabies are very contagious, because a huge number of mites (up to 2 million or more) are present in exfoliating scales.
  • If a person has never had scabies before, symptoms such as itching usually take 2–4 to 6–8 weeks to begin. In a person who has had prior scabies, symptoms usually appear much sooner (1 to 4 days) after exposure. An infested person can spread scabies during the asymptomatic phase.
  • When a person is infected with scabies mites for the first time, symptoms such as itching usually take from 2-4 to 6-8 weeks to begin. In a person who has had prior scabies, symptoms usually appear much sooner (1 to 4 days) after exposure. Scabies can be spread during both asymptomatic and symptomatic phases.
  • Patients/clients are contagious with scabies until the mites and eggs are destroyed by treatment, typically after one course of a topical scabicide (generally 24 hours after treatment) or, sometimes, two courses one week apart. Concurrent disinfestation of clothing and bedding via hot laundering is also indicated.
  • Transmission of scabies can occur in clinical healthcare settings, particularly following long, close patient/client care. Therefore, prophylactic (preventive) treatment may be appropriate for the dental hygienist who has been in close physical proximity with a patient/client with scabies. A primary care provider (e.g., physician or nurse practitioner) should be consulted.
  • Direct contact with infested skin and infested clothing/bedding should be avoided.
  • If you, the dental hygienist, have scabies, you should be treated with a prescription scabicide. In general, a healthcare provider whose role entails close contact with patients/clients can return to work once effective treatment has begun (i.e., typically at least 12 to 24 hours after the application of a topical scabicide; this may be specified as the day after treatment has commenced). Itching may persist for 1 to 2 weeks; this should not be regarded as a sign of treatment failure or re-infestation. The local public health unit can be further consulted regarding any workplace restrictions, particularly in the case of crusted scabies. Persons with crusted scabies are highly contagious, and they should receive prompt treatment to prevent outbreaks.

Oral manifestations

  • No lesions or parasitic infections occur intraorally, except in very rare circumstances.6 However, perioral scratching may result in secondary local infection such as perioral impetigo or cellulitis.
  • Head and neck involvement are rare in adults, but common in infants.

Related signs and symptoms

  • Scabies is one of the most common dermatological (skin) conditions worldwide, and it affects persons of all social classes. While found in every country, it is particularly common in resource-poor tropical settings. Globally, more than 400 million people are affected each year.
  • Scabies can spread rapidly in crowded conditions where close body contact is common. Institutional outbreaks in high-income countries tend to occur in nursing homes, extended-care facilities, and prisons. Childcare facilities also are a frequent site of infestations.
  • The condition is a parasitic infection of the skin caused by a microscopic mite, which burrows into the upper layer of the skin to live and lay eggs. The skin penetration is visible as vesicles, papules, and/or linear burrows.
  • In men, visible lesions are typically found in the finger webs, anterior (inside) surfaces of wrists and elbows, anterior axillary folds, belt line, thighs and external genitalia. In women, lesions tend to be prominent around the nipples and on the abdomen and lower buttocks. Other areas affected in adults and older children include: toe webs, soles of feet, chest, and around umbilicus. In infants and young children, the face, scalp, neck, fingers, palms of hands, and soles of feet are commonly involved — sites that are unusual in adults and older children.
  • Scabies is usually characterized by pruritis (severe itching), particularly at night.
  • In some immunocompromised, elderly, disabled, or debilitated patients/clients7, hyperinfestation (crusted scabies) may appear as a generalized dermatitis, with extensive scaling, crusting, and sometimes vesiculation, and itching may be reduced or absent. Crusted scabies often begins as poorly defined red patches that develop into thick, scaly plaques between the fingers, under the nails, or diffusely over palms and soles. Elbows and knees are also commonly affected, and the nail plates may split due to accumulation of mites in the nail beds. Hair loss can also occur.
  • In most affected persons, scabies is a minor condition that can be readily treated. Complications are usually a result of lesions secondarily infected by scratching. These include impetigo, cellulitis, and, more rarely, septicemia (bloodstream infection), rheumatic heart disease, and kidney damage (including acute and post-streptococcal glomerulonephritis).

References and sources of more detailed information


Date: June 1, 2014
Revised: April 29, 2020; February 6, 2026


FOOTNOTES

1 Diagnosis is based on history and physical examination, often accompanied by a skin scraping or equivalent. The skin sample or suspected mite is examined under microscope to confirm scabies.
2 Treatment of scabies typically entails a topical, often prescription, scabicide (e.g., 5% permethrin cream/lotion in adults and older children, or permethrin or sulfur ointment in infants). In the case of crusted scabies, oral medication (ivermectin) is typically used in conjunction with a topical scabicide and keratolytic cream (e.g., urea).
3 Crusted scabies was formerly known as Norwegian scabies.
4 Animals do not spread human scabies.
5 Some authorities suggest that airborne transmission is also possible.
6 There is at least one published case report of scabies invading gingival tissue.
7 Persons living in nursing homes and/or with dementia may be at elevated risk of crusted scabies, as may be persons with developmental disabilities.


* Includes oral hygiene instruction, fitting a mouth guard, taking an impression, etc.
** Ontario Regulation 501/07 made under the Dental Hygiene Act, 1991. Invasive dental hygiene procedures are scaling teeth and root planing, including curetting surrounding tissue.