Body lice are parasitic insects that live on the body and in the clothing or bedding of infested humans. Infestation is common, found worldwide, and affects people of all races. Body lice infestations spread rapidly under crowded conditions where hygiene is poor and there is frequent contact among people. Body lice are found only in homeless, transient populations who don't have access to changes of clothes or bath.
Infestation is unlikely in anyone who bathes regularly.
Occasionally eggs are attached to body hair. Epidemics of typhus and louse-borne relapsing fever have been caused by body lice. Though typhus is no longer widespread, epidemics still occur during times of war, civil unrest, natural disasters, in refugee camps, and prisons where people live crowded together in unsanitary conditions. Typhus still exists in places where climate, chronic poverty, and social customs prevent regular changes and laundering of clothing. Long-term body lice infestations may lead to thickening and discoloration of the skin, particularly around the waist, groin, and upper thighs.