ScabiesAlso known as Crusted scabies, Norwegian scabies
Scabies is an parasitic infestation that occurs due to an 8-legged mite called Sarcoptes scabiei. It is estimated that about 200 million people suffer from scabies worldwide at any given time and upto 10% of children from poor economic backgrounds tend to be affected by it. Scabies is a highly contagious disease that spreads through prolonged and close physical contact with an infected patient.
Scabies outbreaks are more commonly seen in crowded places such as nursing institutions, daycare centers, prisons, etc., where people live in close proximity to each other. The symptoms of scabies range from a severe itching sensation to the formation of skin lesions such as burrows, papules, crusts, etc. The urge to itch may be especially strong at night.
Scabies is contagious and can spread quickly through close physical contact. Since scabies is a contagious disease , physicians often recommend treatment for entire families or contact groups. Scabies is treated with topical application of anti-scabies creams or lotions. Oral tablets might be required in some cases. It is recommended to simultaneously treat all members living in close proximity to the patient to prevent reinfection.
- All age groups
- Both men and women
World: 200 million (2020)
Bites from other insects mosquitoes, fleas, bedbugs
- General physician
Symptoms Of Scabies
If you have had scabies before, signs and symptoms may develop within a few days of exposure. If you’ve never had scabies, it can take as long as six weeks for signs and symptoms to begin. A person may have scabies if the following symptoms are present:
A severe itching sensation in the affected areas of the skin that usually worsens at night.
Rash or bumps on the skin with a burrow-like appearance.
Although scabies can affect any part of the skin, common sites of infestation are - armpits, between fingers, inner elbows, around the waist, scalp, palms, soles of feet, etc.
Occasionally, there may be scaly patches on the skin that resemble eczema.
A severe type of scabies, called Norwegian scabies, leads to the formation of thick crusts on the skin.
NOTE: In infants and young children, common sites of infestation usually include the scalp , palms of hand, and soles of feet.
Causes Of Scabies
Scabies is not an infection. It is an infestation that occurs due to an 8-legged mite called Sarcoptes scabiei. This mite can enter your skin through direct human-to-human contact with a person with scabies or by sharing personal items, such as bed sheets, towels, linen, etc.
Once the mite comes in contact with human skin, it starts burrowing into the skin’s upper layer and lays eggs. The eggs hatch in a couple of days and develop into adult mites within two to three weeks and spread to other parts of the body.
A severe infestation of scabies known as crusted scabies or Norwegian scabies occurs when the mites and eggs are present in huge numbers. This condition is seen in people with poor or weakened immune systems.
Risk Factors For Scabies
The following conditions increase the risk of contracting scabies -
Living in close proximity to people in overcrowded places, such as nursing homes, prisons, daycare centers, etc.
Sexual relationships with multiple partners.
Sharing toiletries, bed sheets, linen, etc., with other people in the surroundings.
Diagnosis Of Scabies
The physician takes a detailed history of the onset of symptoms and performs a thorough physical examination to identify the site and type of skin lesions. Usually, the close contacts of the person are also examined to check for the spread of scabies.
Scabies can be confirmed by the following tests -
Microscopic examination of a skin scraping
Direct visualization of magnified skin lesions or Dermatoscopy
Burrow ink test to evaluate the burrowing lesions of scabies
Routine laboratory tests or imaging studies play very little role in establishing a diagnosis of scabies. Occasionally, if a patient presents with crusted lesions or Norwegian scabies, routine laboratory tests like Complete Blood Count (CBC) may be performed to get a general idea of the person’s health and immunity status.
Prevention Of Scabies
Scabies is a highly communicable disease that spreads very rapidly by prolonged, close human-to-human contact. It can also spread through fomite contact, such as sharing of items of a personal nature. To prevent the reinfestation or transmission of scabies, the following precautions must be followed:
Do not share items of a personal nature, such as bed sheets, linen, pillow covers, etc., with others, especially anyone with an active infestation of scabies.
Avoid visiting overcrowded areas which have reported an outbreak of scabies.
If you live with someone who has scabies, take care to wash all clothing, towels, etc., with hot water and detergent. Items that cannot be washed must be kept isolated in a separate room for 2-3 days. When the scabies mites cannot be transferred to humans, they eventually die, and the cycle of transmission breaks.
All members of the household must undergo scabies treatment simultaneously if someone in the house has scabies to prevent the reinfection and transmission of the disease in close proximity.
Specialist To Visit
It is essential to seek prompt medical care in presence of symptoms, such as severe itching which worsens at night especially, accompanied by rashes, or other characteristic skin lesions like burrows. A dermatologist and general physician can diagnose and treat scabies.
Treatment Of Scabies
Scabies is treated with topical application of anti-scabies creams or lotions. The creams or lotions must be applied all over the body and not just the area of itch as the scabies mite may be present in different areas of the body. It is recommended to simultaneously treat all members living in close proximity to the patient to eradicate the parasite completely.
The following medicines are used to treat scabies.
- Antiparasitic medications and antipruritics (or anti-itch drugs) are commonly recommended drugs to treat scabies. In some cases, lotions are also advised to relieve itching.
- 5% Permethrin topical preparations are the first line of treatment for scabies and are highly effective in killing the scabies mites.
- Crotamiton formulations are also used which can be applied to scabies lesions.
- 0.5% malathion, 5-10% Sulphur ointment, 10-25% Benzyl Benzoate emulsion are other compounds used for topical application to treat scabies.
- Ivermectin preparations may occasionally be given orally or may be prescribed for topical applications.
- Over-the-counter (OTC) preparations in the form of lotions can be used to provide relief from the skin itch.
Tips to apply anti-scabies topical medications
- After taking a tepid bath or shower and patting your body dry, apply a thin layer of cream/lotion to the whole body from neck down. Avoid applying on your face due to risk of medicine side effects.
Make sure to carefully wash off the ointment after 12 hours.
Reapply the medication topically after 24 hours and follow the same instructions.
Home Care For Scabies
It may take 4-8 weeks for the symptoms of scabies to appear after coming into contact with the mite. As the symptoms start to appear, the severity of the itching sensation starts increasing. Care must be taken to avoid scratching the skin aggressively as it may lead to further irritation, breaking, and bleeding in the skin.
- Application of topical emollient creams and lotions may help the sensation of severe itching subside.
Apply the medicine all over your body from the neck to the toes. Take a bath before applying the prescribed lotions.
As scabies is a highly contagious disease, special care must be taken to break the transmission chain and prevent others around you from getting infected.
It is advisable to seek anti-scabies treatment for all close contacts simultaneously.
At the same time, it is necessary to thoroughly wash all items of personal nature, such as clothes, towels, bed sheets, etc., that you have used in the three days preceding scabies treatment.
Complications Of Scabies
Scabies infestation leads to a severe itching sensation. If the patient does not refrain from scratching aggressively, it may lead to breaking of the skin, which can result in secondary bacterial infection.
Crusted scabies or Norwegian scabies is a type of severe scabies that affects those with weaker immune systems such as HIV patients. There may be millions of scabies mites affecting larger areas and causing a crusty appearance of the skin. Crusted scabies is highly contagious and resistant to treatment.
Alternative Therapies For Scabies
Ayurveda: Ayurvedic formulations, such as lotions, creams, soaps, etc., made from naturally-occurring substances, such as tea tree oil, aloe vera gel, neem oil, camphor oil, eucalyptus oil, turmeric, etc., may provide symptomatic relief to patients with scabies.
These herbal remedies are known for their medicinal properties, and they also give a soothing effect when applied to the skin, reducing the itching sensation.
If you are suffering from scabies, you may get symptomatic relief by applying tea tree oil or aloe vera gel directly to the lesions. You can bathe with soaps made from neem oil extract or eucalyptus oil extract as they are known for their antimicrobial action.
Living With Scabies
Constant itching can considerably hamper the quality of life of a scabies patient. Scabies itch usually worsens at night, and this may disturb the sleep schedule of the patient and leave them feeling restless and tired.
There is also a risk of transmission of scabies from one person to another. Thus, a scabies patient needs to take considerable precautions to avoid the disease transmission. This is especially important if the scabies patient is living in close proximity with other persons in confined spaces.
It is understandable that scabies can lead to isolation and lot of frustration. Proper medical treatment with psyclological support from family and friends can help the patient overcome the condition.
Frequently Asked Questions
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