Human Louse (Head or Body Louse)

Natural Habitat

Exclusively on humans and their clothing. Head lice (P. humanus capitis) live in the hair on the scalp, while body lice (P. humanus humanus) live in the seams of clothing and bedding.

Diet & Feeding

Feeds exclusively on human blood (hematophagy). It is an obligate ectoparasite.

Behavior Patterns

Wingless and cannot fly or jump; they spread through direct contact or sharing of personal items like hats, brushes, or clothing. Females lay eggs called nits, which they cement to hair shafts (head lice) or clothing fibers (body lice). They must feed on blood several times a day to survive.

Risks & Benefits

Risks: Louse bites cause intense itching (a condition called pediculosis), which can lead to scratching and secondary bacterial infections. Body lice are known vectors for diseases such as epidemic typhus, trench fever, and louse-borne relapsing fever. Head lice are a nuisance but are not known to transmit diseases. Benefits: There are no benefits to the human host.

Identified on: 11/16/2025