Crab lice also can infest other hairy parts of the body outside of the pubic area. Anyone may become louse infected under suitable conditions of exposure. Pediculosis is easily transmitted from person to person during direct contact. Head lice infestations are frequently found in school settings or institutions. Crab lice infestations can be found in people living in crowded, unsanitary conditions where clothing is infrequently changed or laundered.
Transmission can occur during direct contact with an invested individual.
Sharing of clothing and combs or brushes may result in transmission. While other means are possible, crab lice are most often transmitted through sexual contact. Usually, the first indication of an infestation is itching. Scratching can be sufficiently intense to result in secondary bacterial infection in these areas. It may be as little as five days or it may take two to three weeks or longer for a person to notice the intense itching associated with this infestation.