If you have lived in a boarding school before, you may be familiar with mites, fleas and bugs that often cause itchy skin or itchy scalp. This could be from hygiene issues or getting infected by others. Now as an adult, you understand how important it is to take care of hygiene as it is among ways to take care of your health. In this article, we will be learning about scabies.
Scabies is an infestation of the skin by the human itch mite known as Sarcoptes scabiei. It typically takes ten minutes of skin-to-skin contact for mites to transmit to another human. This parasite uses their mouths and front legs to burrow into the epidermis (the outer layer of skin) and lay eggs. After 2 to 3 days, the larvae (baby mites) hatch and go to the surface of the skin. Here is where it matures into adults. It will take 1 to 2 months for mites to become adults.
Scabies can be found in many countries. It is estimated to affect more than 200 million people at any time and more than 400 million people in total every year. It is more common in children and young adults. Scabies is one of the commonest skin conditions with the majority in the developing countries. Outbreaks of scabies are a major risk factor for kidney disease in the form of acute post-streptococcal glomerulonephritis. Scabies outbreaks tend to happen in schools, nursing homes, long-term acute care facilities, prisons, retirement homes, hospitals and areas of overcrowding.
Scabies typically is spread by direct, prolonged, skin-to-skin contact with a person who already has scabies. A quick handshake or hug rarely spreads scabies. Scabies is easily spread among household members or sexual partners. Sometimes, scabies is indirectly spread by sharing objects such as clothing, towels or bedding used by an infested person. Indirect spread occurs easily if the infested person has crusted scabies.
Symptoms usually begin 4-6 weeks after infestation. The 3 symptoms of scabies are severe itch that is worse at night, itchy lines (linear burrows) with bumps and tiny blisters with scales. Itching and rash often occur on the wrist, elbow, armpit, webbing between the fingers, nipple, penis, waist, belt-line and buttocks. Scratching can cause skin sores and at times, these sores may be infected by bacteria. Tiny burrows appear as raised and crooked (serpiginous) greyish-white or skin-coloured lines on the skin surface. These burrows most often can be seen in the webbing between the fingers, in the skin folds on the wrist, elbow, or knee. The burrows may also be seen on the penis, breast or shoulder blades. In infants or young children, symptoms are often on the head, scalp, face, neck, palms, ankles and soles.
There is a specific kind of scabies that is only developed by those with suppressed immune systems such as those with HIV, on immunosuppressive therapy, diabetes and older age. These groups of people tend to have the severe scabies known as crusted (Norwegian) scabies. This severe infection can have thousands or millions of mites. This itself can be life-threatening.
Diagnosis of scabies usually is made based on the appearance of the rash and the presence of burrows. When possible, doctors may scrape the skin to look for the mites and its eggs. The skin sample is then examined under a microscope. It is worth noting that a person can still be infected even if mites or eggs cannot be found. Doctors may use dermoscopy to observe the burrow structure.
Scabies can be treated with topical cream or oral medication in severe case. There are many kind of topical treatment that can be prescribed by doctors. This includes permethrin cream, malathion, sulphur and benzyl benzoate. Topical treatment should be applied to all areas of the body from the neck down to the feet and toes. Usually, it need to be left on the body for a certain amount of time before it is washed off. Patient need to wear clean clothes after treatment. It is advisable to wash all bedding and clothing in the house in high temperature on the first day of treatment. Apart from treatment to the infested person, treatment is also recommended for household members and sexual contacts. All persons should be treated at the same time. Anyone who have had sexual contact with infected person within the past 8 weeks should be treated. This helps to prevent reinfestation. Retreatment may be necessary if itching persists more than 2-4 weeks after treatment or if there is new burrows or rash continuously are seen. Complication of scabies such as from sore from scratching, can be treated with antiseptics or antibiotics. It is best to avoid sharing bedding, clothing or towels with someone with scabies. It is important to know that treatment does not kill the parasite’s eggs and treatment should be repeated to kill newly hatched mites.