Itch Mite : Treatements and precautions

There's been a run on anti-itch cream in suburban Chicago as people seek relief from bites thought to be caused by itch mites.

This mite is very seldom seen, lives actually in and on the skin, with the female burrowing tunnels in the upper horny layer, particularly on the front of the wrists, the sides and webs of the fingers, the buttocks, the genitals and the feet. Different varieties of Sarcoptes scabiei (De Geer) are believed to be specific for different mammals, including man and a large variety of domestic and wild animals, but are transferable from one host to another. The variety specific to man is generally referred to as the "itch" or "scab" mite, and acariasis caused by it is sometimes called "scabies." People are most likely to become infested when living in continually crowded quarters, such as slums or jails, or during periods of major calamities that result in prolonged overcrowding.

They are so small that even the adults are barely visible to the unaided eye. Adult females are 0.33 to 0.45 mm long, and the males, 0.20 to 0.24 mm. The mites are a translucent, dirty-white color, with the more highly chitinized (shell or nail like composition) portions brownish. In living specimens, the body is seen to be divided into 2 regions by a fold in the integument (any natural protective covering, such as a skin, rind, or shell); the posterior portion bears the last 2 pairs of the 4 pairs of very short legs. The last 2 pairs of legs do not extend as far as the margins of the body.

Means of Transmission: The ease of transmission of body lice via infested clothing and bedding has led many people to assume that itch mites could be transmitted in the same way. An important difference, however, is that body lice live on their host's clothes and contact his body only to feed, whereas itch mites spend most of their lives beneath the host's skin. Merely putting clothing away for 2 or 3 days at ordinary room temperature should be sufficient to rid it of mites, as they dessicate very easily. Two persons in a bed gave the greatest opportunity for the spread of itch mites. However, transmission is also possible through dancing, flirtation, and ordinary intimate contact between members of a family.

Symptoms of Infestation: Whereas in animals large numbers of mites give rise to "sarcoptic mange," in humans relatively small numbers of mites can cause unpleasant symptoms, and the disease is known as "scabies." At a certain stage, the irritation may become so severe that the patient becomes frantic and suffers from lack of sleep. If the infestation is long continued, or if a later infestation occurs, an allergic reaction develops, with intense itching and a redness, or rash of follicular papules (small blister at the base of a hair) over much of the body. The rash may develop on areas such as around the armpits, the wrists, the waist, inside the thighs, and backs of the calves, but these areas do not necessarily coincide with those of mite infestation. The rash may occur over much of the body, even though only a few mites may be present in restricted locations between the fingers.

Medical Treatment: It is important to diagnose scabies correctly, for neither the irritation nor the liability to skin diseases can cease until the mites have been eliminated. Look for the burrow of a female in such places as between the knuckles and in folds of the wrist and elbow, and then gently prick the burrow open. Toward the end of the burrow, the mite can usually be distinguished as a dull-white spot. Remove it with a needle. A bath before treatment is desirable for hygienic reasons. Thorough treatment is essential, and is best done by a physician or a reliable nurse or orderly. Ramsay recommended that any preparations should be applied in the evening after the patient had taken a warm bath, and that the application be left in place until the next evening, when the treatment would be repeated. All areas of the skin below the neck should be treated, including body folds, palms, and soles. A cleansing bath should be taken 48 hours after the second application. Some tingling of the skin is to be expected after treatment, and it may last as long as 10 to 14 days. Calamine lotion or emulsion may be applied to alleviate this condition. Instructions on the package in which the medication is sold should always be read and followed carefully. Secondary infections may require the skills of a medical doctor or dermatologist. If the treatment is satisfactory and reinfestation occurs, an effort should be made to find untreated persons with whom the patient may have had contact.

Any treament described here should not be taken as policy. You need to see your own doctor if you have a problem.