Head lice are a common concern, particularly among school-aged children. Nits are the eggs laid by head lice. While often confused with adult lice or other scalp debris, recognizing nits is a distinct and important step in identifying a head lice infestation. This article clarifies what nits are, details how to identify them, and explains the implications of finding them in hair.
What Nits Are
Nits are the eggs of head lice, scientifically known as Pediculus humanus capitis. These tiny, oval-shaped structures are the first stage in the head louse life cycle. A female louse firmly glues each nit to an individual hair shaft using a strong, cement-like substance. This adhesive bond makes them difficult to dislodge, unlike ordinary flakes or debris.
Each nit is small, typically measuring 0.8 by 0.3 millimeters, roughly the size of a pinhead or a grain of sand. Their color can vary, appearing yellowish-white, tan, brown, or even blending with the host’s hair color. Viable nits are usually found very close to the scalp, often within 6 millimeters (or 1.5 centimeters) of the skin. This proximity provides the necessary warmth for them to hatch, usually within a week of being laid.
How to Spot Nits
Identifying nits requires careful visual inspection, as they can be easily mistaken for other common hair conditions. A distinguishing feature is their attachment: nits are securely cemented to the hair shaft and do not flake off or move easily when touched. This contrasts with dandruff, which is typically irregular in shape and can be brushed or shaken from the hair. Similarly, dried hair spray droplets or lint will not adhere as stubbornly to the hair strand.
Nits maintain a consistent oval or tear-drop shape, unlike the varied forms of scalp scabs or debris. They are often found in specific areas of the head, with the nape of the neck and the hair behind the ears being common sites. To effectively check for nits, use good lighting, such as natural daylight or a bright lamp. A magnifying glass can assist in seeing these tiny objects more clearly, and a fine-toothed comb can help separate hair strands for a thorough examination. Systematically comb through small sections of hair, inspecting each strand from root to tip.
If You Find Nits
Discovering nits in the hair generally indicates a current or recent head lice infestation. Since nits are laid by adult lice, their presence confirms that lice have been active on the scalp. Nits found further away from the scalp (more than a quarter-inch) may be empty shells from hatched lice or non-viable eggs from an older infestation. However, any nits close to the scalp suggest a more active situation.
Upon identifying nits, the next step involves confirming the finding, possibly by consulting a healthcare professional or a school nurse for an expert assessment. Check other individuals who have had close contact with the affected person, especially family members, as head lice spread primarily through direct head-to-head contact. While this article focuses on identification, finding nits signals the need to seek advice on appropriate treatment and management strategies to address the infestation.