What are crabs?

Crabs (pubic lice) are tiny parasites that can cause itching in the genital area. The lice use their claws to grab and hang on to pubic hairs while feeding on blood.

Who can get crabs and how do they spread?

Pubic lice are common and anyone can get them. Having close bodily contact with another person who is infected spreads crabs. They can survive for some time away from the body so it is also possible to catch them by sharing towels, clothes or someone else's bed or bedding.

What are the symptoms of crabs?

The main symptom of crabs is itching in the pubic or groin area. This is due to irritation from the lice bites. Often the lice can be seen moving in the pubic hair.

Are crabs in the pubic hair the same as lice in the scalp?

No, crabs found in the pubic hair differ from those in the scalp, although pubic lice can sometimes be found in other areas of the body, including the beard, armpits or chest hair and eyelashes.

Who is at risk of crabs?

Anyone who has close physical contact with someone with crabs is at risk of catching them. You can also be reinfected, so it is important to make sure you tell any recent sexual partners that they may have caught crabs from you, and that they are treated. People who share a house or flat with someone who is infected need only be treated if they have slept in the bed or use the towels or clothing of the person who is infected.

What is the treatment for crabs?

There are several over-the-counter shampoos on the market for crabs. Use as directed; reapplication may or may not be necessary. After treatment, egg casings (nits) may remain visible on the hair shaft. To remove these, a fine-toothed comb dipped in vinegar can be used. Shaving off the pubic hair is not necessary.

How do I avoid catching crabs again?

To avoid catching crabs again, people should make sure their sexual partners are treated as well. They should also wash articles that may be infected, such as sheets, towels and clothing, in hot water.

Original material provided by Auckland Sexual Health Service, June 2007. Reviewed by everybody, May 2008.