How can one tell they have lice? - briefly
Persistent scalp itching and the sight of tiny, mobile insects crawling through the hair indicate an infestation. Additionally, firmly attached, oval, white‑to‑yellow nits found within a centimeter of the scalp confirm the presence of lice.
How can one tell they have lice? - in detail
Lice infestations become apparent through several observable signs. The most reliable indicator is the presence of live insects on the scalp or hair shafts. Adult lice are about the size of a sesame seed, grey‑brown, and move quickly when disturbed. Nymphs, smaller and lighter in color, may also be seen.
Nits, the eggs laid by adult lice, are another diagnostic clue. They appear as tiny, oval, translucent or white shells attached firmly to the side of each hair strand, typically within one‑half inch of the scalp. Unlike dandruff, nits do not flake off; they remain glued to the hair shaft and can be felt as a slight bump when running a fingertip along the hair.
Additional symptoms often accompany an infestation:
- Persistent itching, caused by an allergic reaction to lice saliva.
- Redness or small sores on the scalp from scratching.
- A feeling of movement on the scalp, especially when the hair is brushed or the head is tilted.
To confirm the condition, conduct a thorough inspection:
- Separate a small section of hair near the neck and part it with a fine‑toothed comb.
- Examine the comb and hair under good lighting, looking for live lice, nymphs, or nits.
- Repeat the process on multiple sections of the head, including behind the ears and at the crown, where lice tend to congregate.
If live insects or attached nits are found, the diagnosis is clear. Absence of these signs, despite itching, may suggest other scalp conditions, and further evaluation by a healthcare professional may be warranted.