A pubic lice infestation is diagnosed by finding a "crab" louse or egg (nit) on hair in the pubic region or, less commonly, elsewhere on the body (eyebrows, eyelashes, beard, mustache, armpit, perianal area, groin, trunk, scalp). Pubic lice may be difficult to find because there may be only a few. Pubic lice often attach themselves to more than one hair and generally do not crawl as quickly as head and body lice. If crawling lice are not seen, finding nits in the pubic area strongly suggests that a person is infested and should be treated. If you are unsure about infestation or if treatment is not successful, see a health care provider for a diagnosis. Persons infested with pubic lice should be investigated for the presence of other sexually transmitted diseases.
Although pubic lice and nits can be large enough to be seen with the naked eye, a magnifying lens may be necessary to find lice or eggs.