How to check for lice on a person? - briefly
Examine the scalp and hair using a fine-toothed comb, parting sections and looking for live insects, firmly attached eggs, or brown specks near the shaft. Conduct the inspection under bright light after washing and repeat weekly to detect any new infestation.
How to check for lice on a person? - in detail
Detecting head lice on an individual requires a systematic visual inspection combined with appropriate tools. The process begins with preparation, proceeds through a step‑by‑step examination, and ends with verification of findings.
Gather the following items before starting: a bright handheld lamp or daylight source, a fine‑tooth lice comb (minimum 0.2 mm spacing), a magnifying glass (10× optional), a disposable pillowcase or plastic sheet, gloves, and a clean container for collected specimens. Ensure the person’s hair is dry, as wet strands obscure eggs and nymphs.
Begin the examination by parting the hair into sections no wider than two centimeters. Starting at the scalp, run the comb slowly from the root to the tip, wiping the comb teeth onto a white paper after each pass. Repeat this motion across all sections, paying special attention to the nape of the neck, behind the ears, and the crown—areas where lice preferentially attach. Use the magnifying glass to inspect any debris left on the comb for the following indicators:
- Live insects: oval, grayish‑brown, 2–4 mm long, moving quickly when disturbed.
- Nits: oval, white or yellowish, firmly attached to the hair shaft within 1 cm of the scalp; cannot be easily brushed away.
- Empty egg shells: translucent, empty casings that may remain after hatching.
Record the number of live lice and nits observed. The presence of three or more viable nits within 1 cm of the scalp, or any live insects, confirms an infestation. If only a few nits are found without live lice, repeat the inspection after 48 hours to rule out a developing case.
After the assessment, dispose of the comb and any collected material in a sealed bag, wash the examined area with hot water (≥ 60 °C), and advise the individual to repeat the combing procedure every two days for two weeks. Recommend laundering clothing, bedding, and personal items in hot water or sealing them in plastic bags for at least 72 hours to eliminate any surviving stages.