The parasite Sarcoptes scabiei is a tiny skin mite, almost impossible to see without a microscope. It causes a fiercely itchy skin condition known as scabies. Dermatologists estimate that more than 300 million cases of scabies occur worldwide every year. The disease can strike anyone of any race or age, regardless of personal hygiene. Scabies are not the same as body lice.
The microscopic mite is a tiny, eight-legged creature with a round body. The mite burrows between the skin layers. The body develops a reaction to the mite that results in severe itching; often intense enough to keep sufferers awake at night, and frequently leading to skin infections.
Human scabies is almost always caught from another person, anyone who has come into close contact; it could be from a child, a friend, or another family member. Some people do react more severely than others do, and a rare infected person may hardly itch at all.
Attracted to warmth and odor, the female mite is drawn to a new host, making a burrow, laying eggs and producing secretions that cause an allergic reaction. Larvae hatch from the eggs and travel to the skin surface, lying in shallow pockets where they will develop into adult mites. It may be four to six weeks before a newly infected person will notice the itching or swelling that can indicate the presence of scabies. A re-infection will itch right away.
The earliest and most common symptom of scabies is itching, particularly at night. An early scabies rash will show up as little red bumps, like hives, tiny bites or pimples. In more advanced cases, the skin may be crusty or scaly. Scabies will usually begin in the folds and crevices of the body -- particularly between the fingers, under the arms, on the wrists, buttocks or belt line, around the nipples for women and on the penis for men. Mites also tend to hide in, or on, the skin under rings, bracelets or watchbands or under the nails. The head and face are not affected, except in children or those with weak immune systems.
Once diagnosed it is essential that the treatment is properly completed. Thoroughly massage Elimite Cream into all skin surfaces from head to the soles of the feet. It is critical to apply this on every square inch of the body, not only where the rash is. Apply between the finger and toe creases, in the folds of the wrist and waistline, in the cleft of the buttocks and on the genitals and in the belly button. Keep the nails clipped short. Scabies mites can hide under the fingernails. Use a toothpick or old toothbrush to apply beneath the fingernails and toenails.
Leave on overnight, and then remove it by bathing and shampooing (usually sooner for young children). One may notice mild itching, burning or stinging sensation after applying. This is usually just a minor, temporary reaction to the medication. If the hands or any other part of the body is washed during the treatment period, new cream must be reapplied immediately.
The cure rate is 95 % with one application. It is usual for itching and rash to continue for as long as two to four weeks after treatment. Because the 5% of people who are not cured also keep itching, a second application a week later is often advised. In some cases, repeat applications weekly are needed until cured.
Although scabies mites cannot live long without a human host, there have been a few cases of apparent transmission through infested clothing and bedding. Even so, heroic cleaning efforts are generally unnecessary. Normal washing of towels, linens and all clothes used within the previous three days is typically sufficient to prevent re-infestation. The temperature of the wash water doesn't matter, as the mites could not possibly survive a normal washing procedure. Clean clothes or heavy winter jackets and sweaters need not be cleaned. Pesticides should not be used to fumigate the affected areas, as the scabies mite is only contagious if it is already infecting someone.
The itch usually persists for up to a few weeks, even if the treatment worked. To lessen the itch, medications for itch may also be prescribed. Antihistamines and steroids orally or topically will help make it more tolerable. The itch may fade faster if one soaks in a warm tub of water until the fingertips turn into "raisins," then scrub the areas that tend to itch. This will eliminate the dead mites and their debris much faster than allowing them to be shed normally. Occasional patients will have to repeat this once or twice to stop the itch.
Alternate treatments are available, the latest being oral ivermectin pills. This is a new, and probably more effective treatment. It is not yet widely used for ordinary cases of scabies, but will be useful for outbreaks. Some of the older remedies, such as Kwell (lindane), are felt to be too toxic for routine use, but are effective when the Elimite fails (which is rare). Selsun lotion and sulfur ointments are occasionally used.
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