How can the presence of lice in an adult be detected? - briefly
Inspect the scalp and hair with a fine‑tooth comb or magnifying lamp to locate live insects and attached nits; any found specimens can be examined microscopically for definitive identification.
How can the presence of lice in an adult be detected? - in detail
Detecting an infestation of head‑lice in an adult requires a systematic visual and tactile approach, supplemented by laboratory confirmation when necessary.
A thorough scalp examination is the first step. Use a well‑lit area and a magnifying device (10–20× magnification) to scan the hair and skin. Focus on typical habitats: the nape of the neck, behind the ears, and the crown. Look for live insects, which are about 2–4 mm long, gray‑brown, and move quickly. Also search for nits—oval, white or yellowish structures firmly attached to the hair shaft within 1 cm of the scalp. Nits that are firmly cemented cannot be easily displaced; a gentle pull on the hair should not detach them.
A fine‑tooth louse comb (spacing 0.2–0.3 mm) enhances detection. Comb the hair from root to tip in sections, wiping the comb after each pass. Any captured insects or nits should be transferred to a white surface for examination. Repeating the combing process three times increases sensitivity, especially in low‑level infestations.
Tactile assessment adds value. Run fingertips through the hair, feeling for movement or crawling insects. This method is useful when visual cues are obscured by hair density or styling products.
If visual and combing results are inconclusive but symptoms persist (intense pruritus, secondary excoriations), collect specimens for microscopic analysis. Place a few suspect nits or insects on a glass slide with a drop of saline solution, cover with a coverslip, and examine under a light microscope at 40–100× magnification. Identification criteria include the characteristic body shape, six legs, and the presence of a ventral anus in nits.
Environmental inspection supports diagnosis. Examine personal items—hats, scarves, pillowcases, and bedding—for detached nits or live lice. Use a lint roller or adhesive tape on fabric surfaces; press the tape onto suspected areas, then inspect the adhesive under magnification.
Professional evaluation by a dermatologist or trained medical practitioner remains the definitive method when self‑examination is uncertain. Clinicians may employ a dermatoscope for enhanced visualization and can prescribe confirmatory laboratory tests if required.
Combining direct scalp inspection, systematic combing, microscopic confirmation, and environmental checks yields a reliable detection protocol for adult head‑lice infestations.