A hookworm infection caused primarily by the species <i>Ancylostoma duodenale </i> or <i>Necator americanus</i>, usually acquired through penetration of the skin, (often asymptomatic but that can also manifest with an allergic reaction at the site of skin penetration), followed by the migration of larva through the bloodstream to the lungs (causing asymptomatic pneumonitis, eosinophilia) and finally reaching and colonizing the small intestines where they cause blood extravasation leading to diarrhea, abdominal pain, and when untreated, melena, iron-deficiency anemia and protein malnutrition. [from
ORDO]