What is scabies, what are its most prominent symptoms, and how is it diagnosed?

Scabies is a contagious skin condition caused by an infestation of the microscopic mite known as Sarcoptes scabiei var. hominis. This mite burrows into the upper layer of the skin, where it lives and lays its eggs. Scabies can spread easily and quickly, especially in crowded places where there is frequent and prolonged direct physical contact between people [1].

Common Symptoms of Scabies

Symptoms of scabies usually appear 4 to 8 weeks after the initial infestation, although an infected person can transmit the infection during this period even if they have not yet developed symptoms [1]. The most prominent symptoms include:

• Intense itching: This is the most common symptom and is typically more severe at night [1].
• Skin rash: This appears as small, acne-like blisters [2].
• Small burrows: You may notice very thin lines on the skin; these are the tunnels that the female mite digs under the skin surface [1].

These symptoms often appear in specific areas of the body, such as between the fingers, in skin folds at the wrists, elbows, knees, and armpits, on the genitals, nipples, waist, buttocks, and shoulder blades. In infants and very young children, the rash may appear on the head, face, neck, palms of the hands, and soles of the feet [1].

How Does Scabies Spread?

Scabies is primarily transmitted through direct, prolonged skin-to-skin contact with an infected person. Less commonly, it can be spread by sharing clothing, towels, or bedding used by an infected person. Crowded environments such as nursing homes, extended-care facilities, prisons, and childcare facilities are common places for the spread of scabies [1]. It is important to note that animals do not transmit human scabies; scabies that affects animals is caused by a different type of mite that cannot survive or reproduce on humans [3].

Diagnosis of Scabies

A healthcare provider can diagnose scabies based on a physical examination and medical history. The doctor often attempts to confirm the diagnosis by locating the mite itself, its eggs, or its waste (called scybala). The doctor may scrape a small sample of skin or use a needle tip to carefully remove the mite from the end of its burrow, then examine the sample under a microscope to confirm the presence of scabies [1]. However, a person may still have scabies even if the mites, eggs, or waste are not found, as there may be fewer than 10 to 15 mites present on an otherwise healthy infected person [1].

Next Steps and Treatment

If you suspect you have scabies, it is essential to seek medical care (Arabic) to receive an accurate diagnosis and appropriate treatment. The doctor will prescribe a cream, lotion, or oral medication to kill the scabies mites. All household members and close contacts must be treated at the same time to prevent re-infestation and further spread [2]. Additionally, all clothing, towels, and bedding used during the three days preceding the start of treatment must be washed in hot water (temperatures exceeding 50°C for 10 minutes kill mites and eggs) and dried in a hot dryer. Items that cannot be washed or dry-cleaned should be sealed in a plastic bag for several days to a week, as scabies mites typically do not live more than two to three days away from human skin [3].

Medical references

• About Scabies
• Scabies
• Preventing Scabies