How can the presence of lice in a person be determined? - briefly
Detection relies on a thorough scalp examination using a fine‑tooth comb to locate live «lice» and their attached eggs, which appear as oval, white or brown nits cemented within ¼ inch of the scalp. Additional confirmation can be obtained by magnifying the inspected area or by sending collected specimens to a laboratory.
How can the presence of lice in a person be determined? - in detail
Detecting an infestation of head lice requires a systematic approach that combines visual examination, mechanical removal tools, and, when necessary, laboratory analysis.
First, inspect the scalp and hair closely. Use a well‑lit area or a magnifying device to look for live insects, nymphs, or viable eggs (nits) attached to hair shafts near the scalp. Nits appear as oval, tan‑colored structures cemented at a 45‑degree angle to the hair; live lice are small, grayish‑brown insects that move quickly when disturbed.
Second, employ a fine‑toothed lice comb. Run the comb from the scalp outward in sections, wiping the teeth after each pass. Collect any captured specimens on a white surface for easier identification. Repeating the combing process for several days increases detection sensitivity, as newly hatched nits become visible.
Third, consider specialized detection kits. These products contain a transparent solution that stains nits, enhancing contrast against hair and facilitating rapid visual confirmation. Follow manufacturer instructions precisely to avoid false‑negative results.
Fourth, evaluate clinical signs. Persistent itching, especially at night, and the presence of small, red bite marks on the neck, ears, or shoulders support the likelihood of an infestation, though these symptoms alone are not definitive.
Fifth, if ambiguity remains, perform microscopic examination. Collect a sample of hair strands with suspected nits, place them on a slide, and examine under a light microscope at 40–100× magnification. Confirm the presence of viable eggs by identifying an operculum (the cap) and embryonic development within the shell.
Finally, document findings. Record the number of live lice, nits, and affected areas, as well as any symptoms reported. This information guides treatment decisions and helps monitor the effectiveness of subsequent interventions.