Pubic Lice (Crab Lice or Pediculosis Pubis)

Pubic lice (pediculosis pubis or crab lice) are very tiny insects that infest the pubic hair and survive by feeding on human blood. These parasites are most often spread by sexual contact; in a few cases, they may be picked up through contact with infested bedding or clothing. An estimated 3 million people with new cases of the infestation are treated each year in the United States.

Symptoms
The primary symptom of infestation is itching in the pubic area. Scratching may spread the lice to other parts of the body; thus, every effort should be made to avoid touching the infected area, although this may be difficult.

Diagnosis
Pubic lice are diagnosed easily because they are visible to the naked eye. They are pinhead size, oval in shape, and grayish, but appear reddish-brown when full of blood from their host. Nits, the tiny white eggs, also are visible and usually are observed clinging to the base of pubic hair.

Treatment
Lotions and shampoos that will kill pubic lice are available both over the counter and by prescription. Creams or lotions containing lindane, a powerful pesticide, are most frequently prescribed for the treatment of pubic lice. Pregnant women may be advised not to use this drug, and a physician's recommendations for use in infants and small children should be followed carefully. Itching may persist even after the lice have been eradicated. This is because the skin has been irritated and requires time to heal. A soothing lotion such as calamine may offer temporary relief.

Prevention
All persons with whom an infested individual has come into close contact, including family and close friends as well as sex partners, should be treated to ensure that the lice have been eliminated. In addition, all clothing and bedding should be dry-cleaned or washed in very hot water (125° F), dried at a high setting, and ironed to rid them of any lice. Pubic lice die within 24 hours of being separated from the body. Because the eggs may live up to six days, it is important to apply the treatment for the full time recommended.

Information provided by the National Institutes of Health.

Each year, Medical College of Wisconsin physicians care for more than 180,000 patients, representing nearly 500,000 patient visits. Medical College physicians practice at Children's Hospital of Wisconsin, Froedtert Memorial Lutheran Hospital, the Milwaukee VA Medical Center, and many other hospitals and clinics in Milwaukee and southeastern Wisconsin.