Body lice

Body lice are tiny parasites (Pediculus humanus corporis) that spread through close contact with other people.

There are three types of lice:

This article focuses on body lice.

Causes

Lice feed on human blood and live in the seams and folds of clothing for up to 1 month. They lay their eggs and deposit waste matter on the skin and clothing.

You can catch body lice if you come in direct contact with someone who has lice, or with infected clothing, towels, or bedding.

Body lice are bigger than other types of lice.

You are more likely to get body lice if you have poor hygiene or live in close (overcrowded) conditions. Infestation is unlikely to last on anyone who bathes regularly, and who has at least weekly access to freshly laundered clothing and bedding. Placing clothes in a hot dryer helps kill any lice on clothing.

If the lice fall off of a person, they die within about 5 - 7 days at room temperature.

Symptoms

Lice causes severe itching. It is usually worse around your waist, under the arms, near your bra strap, or anywhere clothing is tighter and closer to the body.

You may have red bumps on the skin. The bumps may scab or become crusty after scratching.

Skin around the waist or groin may become thickened or change color if the lice has been there a long time.

Exams and Tests

Your doctor can usually diagnose this condition by looking at your skin and clothing.

  • Full-grown lice are the size of a sesame seed, have six legs, and are tan to greyish-white.
  • Nits are lice eggs. They will most often be seen in the clothing of someone with lice, most commonly around the waist and in the armpits.

Persons with body lice should also be checked for head and pubic lice.

Treatment

Body lice mainly live in clothing. Destroy or carefully wash infected clothing in hot water (at least 130 degrees F), then machine dry using a hot cycle.

Your doctor may also recommend a prescription cream or wash containing permethrin, malathione, or benzyl alcohol.

However, hygiene and washing clothes, bedding, and towels are most important and are usually enough.

Outlook (Prognosis)

With effective treatment, the lice can be completely destroyed.

Possible Complications

Scratching can make your skin more likely to become infected. Rarely, lice may carry uncommon diseases, such as trench fever. Because body lice is contagious, other family members may want to be treated.

When to Contact a Medical Professional

Call your health care provider if you have lice in your clothing or persistent itchiness.

Prevention

Good personal hygiene and effective treatment of infected persons will prevent lice from spreading to others.

Alternative Names

Lice - body; Pediculosis; Vagabond's disease

References

Diaz JH. Lice (pediculosis). In: Mandell GL, Bennett JE, Dolin R, eds. Principles and Practice of Infectious Diseases. 7th ed. Philadelphia, Pa: Elsevier Churchill Livingstone; 2009:chap 293.

Habif TP, ed. Clinical Dermatology. 5th ed. Philadelphia, Pa: Mosby Elsevier;2009: pp 590-594.

Updated: 4/22/2012

Reviewed by: Kevin Berman, MD, PhD, Atlanta Center for Dermatologic Disease, Atlanta, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

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