How do pubic lice manifest? - briefly
Pubic lice cause intense itching in the genital area, often accompanied by tiny gray‑white eggs (nits) attached to hair shafts and reddish bite marks or small papules. The insects themselves appear as crab‑shaped, 1–2 mm darkened bodies that may be seen moving among coarse hair.
How do pubic lice manifest? - in detail
Pubic lice, also known as Pthirus pubis, infest the coarse hair of the genital region, but may also be found on the abdomen, thighs, chest, and occasionally eyebrows or eyelashes. The parasite feeds on blood, causing a characteristic set of clinical manifestations.
Typical signs include:
- Intense pruritus that intensifies several hours after contact with the infested individual.
- Small, gray‑white, oval eggs (nits) firmly attached to the shaft of each hair near the scalp.
- Live adult insects, 1–2 mm in length, appearing as tiny, crab‑shaped bodies moving slowly along hair shafts.
- Red or pink papules and tiny punctate lesions where the insects have bitten.
- Secondary bacterial infection of scratched areas, which may produce crusting, swelling, or pus.
The itching often begins 2–6 days after the initial infestation, coinciding with the emergence of nits and the first adult lice. Lesions are usually confined to the pubic hair zone, but spread can occur to adjacent body hair through direct contact. In some cases, the infestation extends to the scalp or facial hair, especially in children.
Diagnosis relies on visual inspection of hair shafts for live lice and attached nits. Microscopic examination can confirm species identification. Dermoscopy may aid in detecting hidden insects and distinguishing them from dandruff or other debris.
Complications arise when scratching leads to bacterial superinfection, potentially causing cellulitis or impetigo. Rarely, infestation of the eyelashes (phthiriasis palpebrarum) can cause conjunctivitis and corneal irritation.
Effective treatment combines topical pediculicides—such as 1 % permethrin lotion or 5 % malathion shampoo—with thorough removal of nits using a fine‑toothed comb. Re‑treatment after 7–10 days eliminates newly hatched lice. All sexual partners should be treated simultaneously to prevent reinfestation, and personal items (clothing, bedding) must be washed in hot water or sealed for two weeks.