Hookworms: Pets to Humans

The two canine hookworms that have been known to infect humans produce very dissimilar clinical manifestations. Ancylostoma braziliense, a cat and dog parasite of the Gulf Coast and the New World tropics, invades humans percutaneously and wanders in the skin. It does not migrate to the intestine and mature. This species is the major causative agent of human cutaneous larva migrans. In contrast, A. ceylanicum, another cat and dog parasite widely distributed in the Old and New World tropics and subtropics, also invades percutaneously, but it may migrate to the intestine, where it can develop further, becoming a blood-sucking, sexually mature adult parasite. In parts of its geographic range, it ranks with A. duodenale and Necator americanus as a full-fledged parasite of humans; when it is present in sufficient numbers, it causes classic hookworm anemia.

A third hookworm of dogs, A. caninum, is just becoming well recognized as a parasite of humans [1-4]. It is a cosmopolitan species, exceedingly common in both tropical and temperate areas, including North America. It was always considered a host-specific canine parasite that very rarely invaded humans and, when it did, caused essentially asymptomatic infections. The interesting information reported by Croese …