What does a flea feed on when parasitizing humans? - briefly
When a flea infests a person, it pierces the skin and consumes the host’s blood. The meal consists mainly of plasma and red blood cells drawn through the tiny wound.
What does a flea feed on when parasitizing humans? - in detail
Fleas that bite humans obtain nourishment primarily from blood. The insect inserts its piercing‑sucking mouthparts into the skin, rupturing capillaries and drawing a small volume of plasma‑rich fluid. Blood provides the proteins, lipids, and carbohydrates required for development and reproduction.
Key components of the meal include:
- Hemoglobin and other proteins for egg production.
- Glucose and other sugars that supply immediate energy.
- Lipids that contribute to membrane synthesis and storage.
During feeding, the flea secretes anticoagulant saliva to prevent clotting, which can cause localized irritation and a wheal. The bite often results in a pruritic papule that may develop into a small, red bump. Repeated feeding can lead to hypersensitivity reactions in some individuals.
Flea life‑stage requirements differ. Adult females need a blood meal to mature eggs; each engorgement can trigger the production of 20–50 eggs, which are deposited in the environment. Larvae do not feed on blood; they consume organic debris, adult flea feces (which contain partially digested blood), and fungal spores. Consequently, controlling adult feeding on humans reduces egg laying and subsequent infestation cycles.
In summary, the parasite’s diet while attached to a human host consists exclusively of host blood, delivering essential nutrients for survival, reproduction, and the continuation of its life cycle.