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Lice Symptoms and Signs

Patient Comments

Lice infestation on the human body (also known as pediculosis) is very common. Cases number in the hundreds of millions worldwide. While lice can occasionally cause significant illness (typhus, relapsing fever, and trench fever), a lice infestation is generally more of an itchy and embarrassing experience than a serious medical problem. Three distinct presentations of lice infection exist and each is caused by a unique parasite.

Head lice (Pediculus humanus capitis) is by far and away the most common infestation and favors no particular socioeconomic group. A genetically close "cousin," Pediculus humanus corporis, is responsible for body lice and is more commonly associated with poverty, overcrowding, and poor hygiene. Pubic lice ("crabs") is caused by Pthirus pubis and is transmitted by intimate and/or sexual contact.

Lice infestation is a uniquely human experience. Lice do not jump or fly from host to host. They cannot be transmitted via animals but may be transferred by person to person via direct contact and by fomites (inanimate objects -- for example, caps, combs, sheets, etc).

Medically Reviewed by a Doctor on 9/8/2015

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Patient Comments & Reviews

The eMedicineHealth doctors ask about Lice:

Head Lice Infestation - Describe Your Experience

Please describe your experience with head lice infestation (pediculosis).

Head Lice Infestation Advice - Treatment

How did you treat your head lice infestation?

Head Lice - Symptoms

What were the symptoms of your head lice?

Treatment Overview

Itching may continue even after all lice are destroyed. This happens because of a lingering allergic reactionto their bites. Over-the-counter cortisone(corticosteroid) creams or calamine lotion may help. For severe itching, antihistaminemedicines (such as Benadryl) or stronger, prescription-strength corticosteroid creams may be needed. Don't give antihistamines to your child unless you've checked with the doctor first. And don't use cortisone cream for longer than 7 days without talking with your doctor. Do not use the cream on children younger than age 2 unless your doctor tells you to. And don't use it in the rectal or vaginal area in children younger than age 12 unless you've checked with the doctor first.


Read What Your Physician is Reading on Medscape

Lice »

Louse infestation remains a major problem throughout the world. Head louse infestation among school children has reached epidemic proportions in many parts of the United States.

Read More on Medscape Reference »

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