Lice (Pediculosis)

Scientific Name: Pediculus humanus capitis / Pediculus humanus corporis

Order & Family: Order: Psocodea, Family: Pediculidae

Size: 2-3 mm (roughly the size of a sesame seed). Nits (eggs) are much smaller, about 0.8 mm.

Lice (Pediculosis)

Natural Habitat

The scalp and hair of humans (head lice) or the clothing and bedding of humans (body lice).

Diet & Feeding

Obligate parasites that feed exclusively on human blood several times a day.

Behavior Patterns

They cannot fly or jump; they move by crawling. Head lice attach their eggs (nits) to the base of hair shafts with a waterproof glue-like substance. They spread through close personal contact.

Risks & Benefits

Risks include intense itching, scalp irritation, and secondary skin infections from scratching. Body lice can transmit diseases like typhus, though head lice do not. They provide no ecosystem benefits to humans.

Identified on: 3/7/2026