How can you determine if you have lice on your head? - briefly
Examine the scalp and hair with a fine‑tooth comb under bright light, searching for live insects the size of sesame seeds and for oval, yellow‑brown nits attached within a quarter inch of the scalp. Finding either confirms an infestation and warrants treatment.
How can you determine if you have lice on your head? - in detail
Head lice infestations become apparent through a combination of physical signs and systematic examination.
First, observe the scalp for persistent itching that does not improve with typical anti‑itch remedies. Itching often intensifies after exposure to heat, such as a warm shower, because the insects become more active.
Second, inspect the hair closely. Use a bright light source and a magnifying lens or a fine‑tooth comb specifically designed for lice detection. Run the comb from the scalp outward, section by section, paying particular attention to the nape of the neck, behind the ears, and the crown area. The following findings confirm an infestation:
- Live insects, approximately 2–4 mm in length, brown or gray, moving quickly across the hair shaft.
- Nits (lice eggs) attached firmly to the hair shaft within ¼ inch of the scalp. Nits appear as tiny, oval, yellow‑white or brownish bodies; they do not easily slide off when the hair is brushed.
- Empty egg shells (pseudonits) that are brown, translucent, and loosely attached; these are not evidence of active lice but may indicate a past infestation.
Third, feel the scalp for small, moving specks. A gentle fingertip sweep along the hair can reveal lice that are hidden among strands.
Fourth, verify the attachment of suspected nits. Gently pull a hair strand with a suspected nit; if the nit remains attached and does not detach easily, it is likely a viable egg.
If any of the above criteria are met, the presence of head lice is confirmed. For definitive diagnosis, a health professional may examine a sample under a microscope, but the described visual and tactile methods are sufficient for most cases.