Scabies
Scabies Causes
The cause of scabies is the mite Sarcoptes scabiei, of the hominis variety. The infection starts when the female of this species digs into the stratum corneum of a human host's skin and deposits her eggs in the burrow. After 3 to 10 days, the larvae hatches and travels on the skin, molts into nymphal stage, and then matures into adult mites. Typically, adult mites settle on the host's skin for 3 to 4 weeks. The action of the mites moving about on the skin produces a deeply itchy rash on the host's skin. Meanwhile, the eggs deposited in the skin causes an immensely adverse allergic reaction which also results in an intense itch. Scabies is easily transmitted through skin to skin contact with an infected person. Often, the infection is spread throughout members of one household or individuals sharing close quarters. Since scabies outbreaks mostly affect bed partners, it is sometimes considered a sexually transmitted disease. In addition, scabies can be spread via contact with infected clothes, beddings, or towels, although transmission through this mode has less significant risk.
Scabies Definition
Scabies is a contagious ectoparasite infection of the skin characterized by intense itching, superficial burrows, and secondary infections. The term comes from the Latin word ?scabere? which literally means ?scratch?.
Scabies Diagnosis
Diagnosis of scabies can be done by finding the characteristic burrows. However, this often proves difficult because the burrows are typically scarce or obscured by other skin marks (such as scratch marks or other unrelated skin irritations). If burrows are not identified in the itchy areas, the body's entire skin surface should be thoroughly examined. Ink or a topical tetracycline solution may be rubbed on areas suspected of scabies infestation. If scabies infection is present, the examined skin will show a characteristic zigzag or S pattern of the burrow. To confirm the diagnosis, a microscopy can be done on surface scrapings to screen for mite, ova, or fecal pellets.
Scabies Symptoms and Signs
Classic presentations of scabies are the appearance of an intensely itchy rash and superficial burrows. These symptoms typically appear after 4-6 weeks from the infestation. An infected individual may have already been contagious for that period before a definite diagnosis was made. The mite that causes scabies often burrow in the webs of fingers, wrists, elbows, armpits, female areolas, male genitalia, along the belt line, and on the lower part of the buttocks. In some cases, a tiny mite is visible at the end of a burrow. The burrows often appear as tiny, barely visible skin bumps on the affected areas. As the infection worsens, these small bumps may become reddish and more intense. In some cases, the characteristic rash is secondarily infected as a result of persistent scratching breaking the skin and opening it up to other infections. In addition, widespread rashes and thick scaling may occur in people with reduced immunity, in which case the infection is called Norwegian scabies.
Scabies Treatment
Scabies can be treated topically or orally. Topical therapy may consist of Permethrin, Eurax, Malathion, and Lindane being applied on the affected areas. Oral medications are also used to treat the infestation. A single dose of ivermectin has been documented to cure the infection.
Drugs used for treatment of Scabies
Elimite