Pubic lice are small, wingless insects most often found in the genital area of humans. When a person is infested with lice (whether it is pubic lice,
head lice, or
body lice), the condition is known as pediculosis. An infestation with pubic lice is known as pediculosis pubis.
They are not the same thing as head lice.
Lice found on the hair and head are caused by an infestation with a parasite known as
Pediculus humanus capitis.
Pubic lice also goes by several other names, including:
- Pubic crabs
- Crabs
- Crab lice
- Genital crabs.
Pubic lice is usually spread through sexual contact. For this reason, it is considered a sexually transmitted disease (STD). In rare cases, infestation can be spread through contact with an infested person's bed linens, towels, or clothes. Infection in a young child or teenager may indicate sexual activity or sexual abuse. Animals do not get or spread pubic lice.
There are several risk factors for pubic lice. These include:
- Having multiple sex partners
- Sharing clothing or bedding with an infested person
- Having sexual contact with an infested person
- Being a sexually active adolescent.
There are three forms of pubic lice:
- The egg (also called a nit)
- The nymph
- The adult.
The Nit
Nits are the eggs of pubic lice. They are very small (about the size of a knot in thread) and are hard to see. They are oval and usually yellow to white in color. Nits take about one week to hatch. Once hatched, they are white or clear in color.
Nymph
The nit hatches into a baby pubic louse called a nymph. It looks like an adult pubic louse, but is smaller. To live, the nymph must feed on blood.
Adult Pubic Louse
The adult louse is about the size of a sesame seed, has six legs, and is tan to grayish-white in color. To live, adult lice need to feed on blood. If the pubic louse does not get a blood meal, it dies within one to two days.
The most common symptom of pubic lice is frequent, intense itching. This is because the saliva of the pubic lice causes an allergic reaction.
Pubic lice are generally found in the genital area on pubic hair, but may occasionally be found on other coarse body hair, such as hair on the legs, armpits, mustache, beard, eyebrows, or eyelashes. Infestations of young children are usually on the eyebrows or eyelashes.
An infestation is diagnosed by looking closely through pubic hair for nits, nymphs, or adults. It may be difficult to find nymphs or adults; there are usually few of them, and they can quickly move away from light. If crawling lice are not seen, finding nits confirms that a person is infested and should be treated.
Nits and pubic lice are usually visible to the naked eye, but a hand lens or light may help.
Pubic lice is treated with medication, which is generally effective, as long as the person follows the directions on the bottle exactly. Current medications available for treating pubic lice include:
- Pyrethrin (such as Rid®, A-200®, Clear®, and R&C®)
- Permethrin (Nix®)
- Lindane (Kwell®) -- available by prescription only.
To kill any lice or nits attached to hairs that may be left on clothing or bedding, machine-wash any washable items that the infested person used during the two to three days before treatment. Make sure to use the hot water cycle (130°F). Dry laundry using high heat for at least 20 minutes.
