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Body lice

Definition

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

There are three types of lice:

• Body lice
• Head lice
• Pubic lice

This article focuses on body lice.

Alternative Names

Lice - body; Pediculosis

Causes, incidence, and risk factors

Lice feed on human blood and live in the seams and folds of clothing. 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.

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

Symptoms

Intense itching is the main symptom. It is usually worse at the waistband, in the armpits, at the bra strap, or anywhere clothing is tighter and closer to the body.

Red bumps appear on the skin. They may become crusted or scabbed from scratching.

Areas around the waist or groin may become thickened or discolored when lice have been present for a long time.

Signs 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.

Support Groups

Expectations (prognosis)

With effective treatment, the lice can be completely eliminated.

Complications

Another (secondary) skin infection may occur from scratching. In rare cases, body lice may carry uncommon diseases, such as relapsing or trench fever. Because body lice is contagious, other family members may want to be treated.

Calling your health care provider

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.

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.