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hookworm hook·worm (huk'wûrm')
Any of numerous small parasitic nematodes of the family Ancylostomatidae having hooked mouthparts with which they fasten themselves to the intestinal walls of various hosts, including humans.
hookworm disease n.
A disease resulting from infestation with hookworms and usually marked by abdominal discomfort, diarrhea, and anemia.
a parasitic infestation of humans, dogs, or cats caused by bloodsucking worms (see ) living in the small intestine-sometimes associated with secondary anemia. Several species of hookworm can cause the disease. Necator americanus, which ranges in size from 5 to 11 millimetres (0.2 to 0.4 inch), is responsible for about 90 percent of human hookworm infections that occur in tropical and subtropical regions of the world. Ancylostoma duodenale, 8 to 13 millimetres long, is found on all continents but is most prevalent in warm regions. A. braziliense, from 8 to 11 millimetres long, is normally parasitic in dogs and cats; man, however, is sometimes infected by this species in the southern United States, South America, and Asia. A. ceylanicum, normally parasitic in dogs, is sometimes found in man in South America and Asia. A. duodenale, possesses four hooklike teeth in its adult stage, and N. americanus has plates in its mouth rather than teeth.