Louse (Head louse)
Scientific Name: Pediculus humanus capitis
Order & Family: Order: Psocodea, Family: Pediculidae
Size: 2.1 to 3.3 millimeters (approximately the size of a sesame seed)
Natural Habitat
Found exclusively on the human scalp and hair shaft
Diet & Feeding
Hematophagous; feeds on human blood several times a day
Behavior Patterns
Crawls and climbs (cannot jump or fly); females lay eggs (nits) at the base of hair shafts. They are highly specialized parasites.
Risks & Benefits
Risks include intense itching (pruritus) due to allergic reactions to saliva, and potential secondary bacterial skin infections from scratching. They do not transmit diseases but cause significant social distress.
Identified on: 5/18/2026