Pubic lice (often called "crabs" because of their
crab-like appearance under a microscope) are six-legged
creatures that infest the hair in the pubic area.
They can also infest other body hair, but they prefer
the pubic region. Although pubic lice infestation,
, is considered a sexually
transmitted disease (STD), it can be contracted in
What Are the Signs and Symptoms? Each female
pubic louse (the singular of lice) lays about 30 eggs
(called nits) - about two to three per day
- over its lifespan. The eggs hatch in about 10 days.
If the infestation consists of many adult lice, symptoms
may be noticeable immediately. But if the infestation
initially involves a few lice that then lay eggs,
a person may not experience any symptoms for 2 to
4 weeks until the eggs hatch.
Although it's possible to be infested with pubic
lice and have no symptoms, people with pubic lice
usually experience itchiness. This can worsen at night
when the lice become active and bury their heads inside
pubic hair follicles to feed on human blood.
Sometimes, lice bites can also cause the infested
area to become inflamed because of a reaction to the
proteins in the saliva of the louse. Constant itching
and scratching can cause the area to become raw, resulting
in a secondary bacterial infection. Scratching can
also help the pubic lice to spread.
If lice infest the eyebrows or eyelashes, the eyes
may also become inflamed.
How Are They Diagnosed? An examination of
the external genital region infested with pubic lice
can show small gray-white oval eggs (nits) attached
to the hair shaft and may reveal adult lice.
Adult pubic lice can be easily identified under the
microscope, but they can be difficult to see with
the naked eye because of their location and appearance.
Gray-white pubic lice blend in with white skin, and
brown lice can be mistaken for moles and are hard
to see on black skin.
The doctor may also notice scratch marks and secondary
bacterial infections such as impetigo. In young children,
pubic lice may also be a cause of blepharitis
(irritation or infection of the eyelids). So, a child's
eyelashes should be examined with a high-powered magnifying
glass if lice are suspected.
Are They Contagious? Pubic lice are usually
transmitted through direct physical contact, especially
with the genital area. Occasionally, transmission
can occur through contact with the infested person's
sheets, towels, or clothes. (Pubic lice are capable
of reproducing about 2 weeks after they're born, but
they can live apart from a human body for only 1 to
2 days. Nits live no longer than a few days in clothing
But contrary to what some people may think, pubic
lice are rarely transmitted from furniture or toilet
seats - because the lice that fall from the body are
usually injured or dying. Unlike fleas, lice can't
jump from person to person. And they can't be contracted
Can a Pubic Lice Infestation Be Prevented?
Because pubic lice are considered an STD, an infestation
can be avoided by not having sex or by having sex
only with one uninfested partner.
Pubic lice can also be contracted from bedding and
towels used by an infested person, so it's important
to avoid contact with any item - including clothing
- that a person who's infested has used.
How Are They Treated? Normally, an infestation
of pubic lice does not require professional treatment.
Pubic lice can be treated with over-the-counter medicated
shampoos used to treat head lice.
Check the product label or ask your child's doctor
if the treatment is gentle enough to use in the pubic
area. (It's important to note, though, that lice treatments
containing the pesticide lindane are not recommended
in the United States.)
Following the shampooing, comb the pubic hair with
a fine-tooth comb to remove nits. Applying vinegar
to the pubic hair may help loosen the eggs, but the
hair should be dry before applying the shampoo. Though
one application is usually all that's needed, your
child's doctor may recommend another treatment 1 to
2 weeks after the initial infestation to break the
cycle. Medicated shampoos, creams, and lotions can
get rid of the lice immediately, but it may take several
weeks for the itching and irritation to go away.
If the infestation is substantial, you may want to
visit your child's doctor for a prescription-strength
treatment shampoo that you can use at home. If the
area is raw or has open lesions from scratching, antibiotics
may be prescribed for a secondary bacterial infection
that may be present.
Because pubic lice can live in bedding and clothing,
these items must be treated to stop the infestation.
Wash all clothing and linens in hot water, then put
them in the hot cycle of the dryer for at least 20
minutes. Items that can't be washed can be sealed
in airtight plastic bags for 10 to 14 days before
It's also important to make everyone who has come
in contact with the infested person or the infested
linens aware of the infestation so they can also be