Where are lice located? - briefly
Lice are external parasites that inhabit the skin, hair or feathers of their hosts. Typical sites on humans include the scalp, body hair, and, for pubic lice, the genital area or clothing.
Where are lice located? - in detail
Lice are obligate ectoparasites that reside on the external surface of their hosts. Their preferred sites vary by species:
- Head lice (Pediculus humanus capitis) – attach to the scalp, embed their eggs (nits) in the base of hair shafts, and remain within a few centimeters of the hairline. They avoid areas with dense body hair, such as the beard or chest.
- Body lice (Pediculus humanus corporis) – live in the seams of clothing, particularly undergarments and outer garments, and only move onto the skin to feed. They are common among individuals with poor hygiene or crowded living conditions.
- Pubic lice (Pthirus pubis) – inhabit coarse hair of the genital region, as well as axillary, facial, and chest hair. They cling close to the skin surface and lay eggs near the hair roots.
In addition to these primary habitats, lice can be found in environments that support their life cycle. Infested clothing, bedding, towels, and upholstered furniture provide temporary refuge for eggs and nymphs, especially for body lice. The microclimate of these substrates—warm, humid, and protected from direct sunlight—facilitates development from egg to adult.
The adult insects remain on the host for feeding, typically taking short blood meals several times a day. After feeding, they retreat to the same attachment site to lay eggs, ensuring continuity of the infestation within the localized region.