Trauma to the gut resulting from feeding activities of hookworm was investigated in dogs infected via duodenal puncture or per os with adult worms in gelatine capsules and killed at intervals ranging from 2 to 24 hours and at daily intervals of 1 to 17 days. Mechanical trauma is a local phenomenon involving about nine villi in maximally developed lesions. Formation of a microabscess deep in the lamina propria with overlying confluent villi and profusely sloughing epithelium and stroma signal the end of an attachment period. While each worm may produce as many as six deep lacerations or numerous shallow ones per day, repair of these sites occurs quickly, precluding ulceration with persistent bleeding. Hemorrhage associated with attached hookworms when numerous may be of considerable importance; upon detachment of the parasites, however, the transience of the lesions renders blood loss and impaired absorptive function of relatively secondary importance in the pathogenesis of hookworm anemia.
Present address: Department of Parasitology, College of Veterinary Medicine, University of Georgia, Athens, Georgia 30602.