What are crab or pubic lice (Pthirus pubis)?
Pubic (crab) lice are tiny (1-2 mm) blood sucking insects. The common name pubic louse (“louse” is the singular form of the word “lice”) comes from where they are typically found — in the pubic area of infested individuals. They may also be found in armpit, chest and eyelash hair. The common name crab louse describes their overall shape along with two pairs of enlarged claws, features which resemble real crabs. These modified claws are better adapted to grasp coarse hairs and this is one reason why pubic lice occur where they do. This tiny insect has been a highly specialized “companion” of humans, and our primate cousins, since before recorded history. Pubic lice bite to get blood. The bite leaves an intensely itchy lesion but, unlike some other blood-feeding insects, pubic lice do not transmit diseases. Scratching to relieve the intense itch can result in secondary infections, however. Pubic lice are found worldwide and are frequently spread through sexual contact.
Pubic (crab) lice are tiny (1-2 mm) blood sucking insects. The common name pubic louse (“louse” is the singular form of the word “lice”) comes from where they are typically found — in the pubic area of infested individuals but they may also be found in armpit, chest and eyelash hair. The other common name crab louse describes their overall shape and the two pairs of enlarged claws, features which resemble real crabs (see photo right). These modified claws are better adapted to grasp coarse hairs and this is one reason why pubic lice occur where they do. This tiny insect has been a highly specialized “companion” of humans, and some of our primate cousins such as gorillas and chimpanzees, since before recorded history.
