Scabies is a common skin condition resulting from an infestation by a tiny, eight-legged mite known as Sarcoptes scabiei var. hominis. These microscopic mites burrow into the outermost layer of human skin, where they live and lay eggs. The body’s immune response to the mites, their eggs, and their waste products triggers the characteristic symptoms, primarily intense itching and a rash. This condition is highly contagious.
Understanding Scabies and Genital Involvement
Scabies mites do not infest the internal mucous membranes of the vagina. The mites require the outer layer of skin, the stratum corneum, to burrow and survive. However, scabies can certainly infest the skin of the external genital area, which includes the vulva, labia, penis, scrotum, and perineum.
Recognizing the Signs
Recognizing the signs of scabies involves observing specific dermatological changes. The most common symptom is severe itching, which often intensifies at night or after a warm bath or shower. This intense itching is an allergic reaction to the mites and their byproducts.
Accompanying the itching is a pimple-like rash, which may appear as small, red bumps or blisters. In the genital region, these lesions can manifest on the vulva, labia, penis, or scrotum, sometimes appearing as inflamed bumps or nodules.
A distinguishing feature of scabies is the presence of tiny, raised, grayish-white or skin-colored lines, known as burrows, which are tracks where the female mites have tunneled just beneath the skin’s surface to lay eggs. These burrows are often subtle and can be obscured by scratching, which may also lead to secondary bacterial infections. Symptoms can take two to six weeks to appear after a first infestation.
How Scabies Spreads
Scabies primarily spreads through prolonged and direct skin-to-skin contact with an infested individual. Sexual contact is a common mode of transmission for genital scabies due to the intimate and extended skin-to-skin proximity involved.
While direct contact is the main pathway, scabies can less commonly spread through sharing personal items like clothing, bedding, or towels that have been recently used by an infested person. However, this indirect transmission is less frequent because the mites typically survive only for about two to three days away from a human host. Casual contact, such as a quick handshake or hug, is generally insufficient for transmission.
Diagnosis and Treatment
Diagnosing scabies typically begins with a healthcare provider visually examining the affected skin and inquiring about symptoms, particularly the characteristic intense itching that worsens at night. To confirm the presence of mites, eggs, or fecal matter, a doctor may perform a skin scraping. This involves gently scraping a suspected area of skin and examining the sample under a microscope.
Treatment for scabies involves prescription medications called scabicides, which are designed to kill the mites and their eggs. Permethrin 5% cream is a common first-line topical treatment, usually applied to the entire body from the neck down and left on for several hours before washing off. Oral medications like ivermectin may be prescribed for more severe cases, such as crusted scabies, or when topical treatments are not suitable.
It is crucial to treat all close contacts and household members simultaneously, even if they show no symptoms, to prevent re-infestation. Additionally, washing all bedding, clothing, and towels used in the three days prior to treatment in hot water and drying them on high heat helps eliminate any remaining mites in the environment.