Scabies (aka “the itch”) is a highly contagious and common skin disease characterized by small, red itchy bumps and rashes on the outer layer of the skin. As the name suggests, the disease causes extreme itching for sufferers, particularly at night. Scabies is caused by tiny,eight-legged female mites (formally named sarcoptes scabiei) that burrow on to skin shortly after mating and fertilization. The female mites then lay up to three eggs a day for the duration of their lifetime (approximately 1-2 months). The eggs then develop into adults in about 10-14 days. Newly infected individuals may not see symptoms for up to 4-6 weeks.
Scabies is normally spread through lengthy skin-to-skin contact between individuals such as sexual parners and household members. It can also be spread through sharing beds, clothing, towels, and other personal items. It is believed to be more common in winter because that is when people are more likely to be indoors and in close proximity to each other. Anyone can get scabies, including those who stay very clean; it is not believed to be related to personal hygiene. The worst itching, however, seems to occur in children and older adults. Children also have worse skin reactions. Scabies is particularly widespread in countries with high population densities and limited medical facilities. It is estimated that one out of 1,000 people are infected with scabies each month.
Early symptoms of scabies appear in the form tiny red bumps or pimples but in more advanced cases the skin may become crusty or scaly. Crusted scabies (aka “Norwegian Scabies) is more severe and highly contagious and is caused by thousands or even millions of mites. It is uncommon, however, and tends to affect older people or those with other ailments and weakened immune systems. Folds and crevices in the body such as in the armpits, between the fingers, under fingernails, and on the wrists and buttocks are prime locations for mites to hide. These tend to be the areas where scabies normally begins. The reason for this is that the mites prefer warmth and smell. The face and scalp are not normally affected by scabies.
Scabies is diagnosed by scraping off a small sampling of dry skin from an affected area and observing it under a microscope for signs of mites. Besides itching and burrows on the skin, other signs and symptoms of scabies include rashes in the form of tiny, itch red bumps on the limbs and trunk, lumps in the armpits and groins and along the shaft of the penis, blisters on the palms and soles in infants, and the development of secondary infections such as impetigo and cellulitis. Itches may break when scratched and itchy skin may become thick and scaly and/or crisscrossed with scratch marks.
Scabies is treated mainly through the application of scabicides (i.e. chemical insecticides) or special creams and lotions (e.g. 5% Permethrin creams like Elimite) as prescribed by physicians. In certain cases, pills may needed to be taken as well. Care should be taken, however, as not all scabies medicines are safe for everyone and some have side effects. For this reason, it is imperative to follow a doctor’s advise precisely. All infected persons within a household should be treated at once to prevent it from spreading again. Bedsheets, clothing, towels and personal effects must all be washed thoroughly. Following treatment, itching may continue for another 2-4 weeks. If itching persists beyond four weeks, an alternative form of treatment may need to be prescribed.