How to distinguish fleas from lice on a person by photo? - briefly
Fleas are larger (1.5–3 mm), dark‑brown, laterally flattened insects that jump and are typically seen on lower legs or clothing. Lice are smaller (1–2 mm), elongated gray‑white parasites that remain attached to hair shafts near the scalp or body hair.
How to distinguish fleas from lice on a person by photo? - in detail
Fleas and head‑lice differ markedly in size, shape, color, and typical location on the body, making visual identification possible when a clear photograph is available.
Fleas are usually 2–5 mm long, laterally flattened, and have a dark, hard exoskeleton. Their bodies taper toward the rear, and they possess strong hind legs adapted for jumping. In a photo, fleas appear as compact, oval silhouettes with visible antennae and segmented legs. They are most often captured on the skin of the lower limbs, around the ankles, or on clothing, especially where the fabric is tight against the skin.
Head‑lice are considerably smaller, measuring 1–3 mm, with a more rounded, elongated body that is softer and lighter in color—typically tan to gray. They have a distinct head and a body that is not as flattened as a flea’s. In images, lice show a clearer separation between head and thorax and lack the powerful hind legs of fleas. They are almost exclusively found on the scalp, hair shafts, or eyebrows, clinging close to hair strands.
Key visual criteria for differentiation:
- Size: Fleas exceed 2 mm; lice stay below 2 mm.
- Body profile: Fleas are laterally compressed; lice are more cylindrical.
- Leg structure: Fleas possess enlarged hind legs for jumping; lice have uniformly sized legs without specialization.
- Color and texture: Fleas display a darker, glossy exoskeleton; lice are lighter and less reflective.
- Location on the host: Fleas appear on bare skin or clothing near lower extremities; lice are confined to hair-bearing regions, especially the scalp.
When evaluating a photograph, zoom in to assess the insect’s silhouette, count visible segments, and note the surrounding area. A flea will be positioned on exposed skin or fabric, often near a bite mark, while a louse will be embedded in hair, close to the scalp. Using these morphological and locational cues enables reliable distinction without physical examination.