Head Louse (plural: Head Lice)

Exclusively on the human scalp and hair, where they remain close to the skin for warmth and food.

Obligate parasites that feed exclusively on human blood several times a day.

They are wingless and cannot jump or fly; they move by crawling. Females lay eggs (nits) firmly glued to the base of hair shafts. They spread primarily through direct head-to-head contact.

They cause intense itching (pruritus) due to an allergic reaction to their saliva. While they are a nuisance and can lead to secondary skin infections from scratching, they are not known to transmit bacterial or viral diseases.