Scabies

Symptoms: Intense itching, linear or curved skin burrows, papules on various parts of the body 

Causes: Sarcoptes scabiei var. hominis mite infestation

Risk Factors: Close skin-to-skin contact with an infected person, crowded living conditions, fomite transmission, weakened immune system

Prevalence: Worldwide- 200 million

Severity: Mild to severe

Which doctor to consult: Dermatologist, General Physician

Overview:

Scabies is an infestation of the skin by a tiny burrowing mite called Sarcoptes scabiei var. hominis. These microscopic mites burrow into the upper layer of the skin, where they live and lay their eggs. 

The most common symptoms of scabies include intense itching and papules (small, raised bumps). Excessive scratching can lead to skin breakage and infections like impetigo (bacterial skin infection).

Scabies is extremely contagious and can spread quickly through close person-to-person contact. It commonly spreads within families, childcare groups, schools, nursing homes, and prisons.

To prevent transmission of scabies, avoid close contact with someone who has scabies and avoid sharing personal items. Treatment for scabies includes topical creams and oral medication. 

Symptoms:

Here are the key symptoms of Scabies:

• Intense itching in the affected area, which may be stronger at night.

• Linear or curved skin burrows may be visible. These are the tunnels created by the mites as they burrow under the skin.

Scabies presents as red papules (small, raised bumps) on the skin. These scabies lesions can occur on various parts of the body, including:

• Wrists and armpits

• Belly button

• Buttocks

• Elbows

• Waist

• Breasts in females

• Genitals

• Palms and soles

• Web spaces of fingers and toes

Causes:

Scabies is caused by the Sarcoptes scabiei mite. These tiny, eight-legged mites burrow just under the skin, creating tunnels where they lay eggs. The female mite is responsible for burrowing and laying eggs, and the eggs hatch into larvae. These larvae then travel to the surface of the skin and mature. The intense itching occurs in the area where the mite burrows and scratching is often stronger at night. These mites can then spread to other areas of the skin or other people’s skin.

Risk Factors:

The risk factors associated with scabies:

Skin-to-Skin Contact: Scabies is most commonly transmitted through prolonged skin-to-skin contact with an infected person. Sexual partners can also transmit the mite to each other. Even if symptoms take weeks to develop, carriers can unknowingly spread the infestation.

Crowded Living Conditions: People living in crowded spaces, such as dormitories, nursing homes, or refugee camps, are at greater risk due to close proximity and frequent contact with others.

Fomite Transmission: Scabies can also spread indirectly through contact with contaminated items (fomite transmission). Furniture, bedding, towels, and clothing infested with Sarcoptes scabiei mites can transmit the parasite. Proper sanitation of these items is crucial to prevent reinfection.

Weakened Immune System: Individuals with weakened immune systems, such as the elderly, those with HIV/AIDS, lymphoma, leukaemia, or organ transplant recipients, have an increased risk of getting scabies. Crusted scabies, a severe form, is especially contagious.

Possible Complications:

Excessive scratching can lead to skin breakage and infections like impetigo. Impetigo is an infection on the skin’s surface primarily caused by staph (staphylococci) bacteria or sometimes by strep (streptococci) bacteria.

Crusted scabies is a more severe form of scabies that can affect some persons, such as:

• Individuals with weakened immune systems, such as those with HIV or lymphoma or recipients of organ transplants

• Young children

• People with developmental disabilities

• Individuals who are very sick, such as those in nursing homes or hospitals

• Older people in nursing homes

Crusted scabies make the skin scaly and crusty and affect large areas of the body. It can be challenging to treat and is highly contagious. It requires prompt treatment with a prescription pill and a skin cream. A person with scabies often has about 10 to 15 mites. However, a person with crusted scabies may have millions of mites. However, there might be no itching or may be mild. Remember that early recognition of scabies signs and timely treatment are crucial to prevent complications. If you suspect scabies, seek medical advice promptly.

Prevention:

Scabies is primarily transmitted through direct, prolonged skin-to-skin contact with an infested person. It can also spread through sharing of items or exposure to items such as clothing, bedding, or furniture used by an infested person.  To prevent transmission or reinfestation of scabies, follow these steps:

• Avoid close contact with someone infected with scabies.

• Avoid sharing personal items.

• If someone in your household has scabies, it is essential to treat all household members, especially those who have had prolonged skin-to-skin contact. Treating everyone simultaneously helps prevent reexposure and reinfestation.

• Wash all clothing, towels, and bedding used within three days before treatment with hot, soapy water. Dry them with high heat to kill mites and their eggs. Dry-clean items that cannot be washed at home.

• Items that cannot be laundered can be disinfested by sealing them in a closed plastic bag for several days. Scabies mites generally do not survive more than 2 to 3 days away from human skin.

• Cleaning your house is a good idea to stop scabies from spreading. This is especially valid for crusted scabies patients. Vacuum floors, carpets, and furniture to get rid of scales and crusts that could contain scabies mites.

When to see a doctor?

If you notice any symptoms of scabies or suspect exposure, consult a doctor as there is no over-the-counter cure for scabies. Early diagnosis helps ensure proper treatment and prevents the spread of mites to others or other parts of your skin. If you have been exposed to scabies, you can still spread it even before symptoms appear. Therefore, seeking medical advice is essential.

Diagnosis:

To diagnose scabies, your healthcare provider examines your skin for symptoms of mites. They look for the signs such as burrows, itchy papules and nodules.

Microscopic Examination: In some cases, your healthcare provider may take a sample of your skin (usually from a burrow) and examine it under a microscope. This allows them to check for the presence of mites or their eggs.

Treatment:

The treatment options for scabies include:

Topical creams and lotions: These are available by prescription. Apply it all over your body (from the neck down) and leave it on for a recommended time before washing it off. The topical medications include the following: 

• 5% Permethrin cream

• 0.5% Malathion lotion

• 10-25% Benzyl benzoate emulsion

• 5-10% Sulfur ointment

Oral medication: Ivermectin is an oral medication that may be prescribed if the patient’s immune system is altered.