Ancylostoma

Ancylostoma is a genus of parasitic nematodes known as hookworms, belonging to the family Ancylostomatidae. The genus includes several species that infect mammals, including humans, dogs, and cats. In humans, the most relevant species are Ancylostoma duodenale and, in some regions, Ancylostoma ceylanicum. Other species such as Ancylostoma caninum, Ancylostoma braziliense, and Ancylostoma tubaeforme primarily infect animals but can cause disease in humans, most notably cutaneous larva migrans.

Lifecycle and transmission

Ancylostoma species have a life cycle that begins with eggs shed in the feces of an infected host. In the environment, eggs hatch into rhabditiform larvae, which may molt into infective filariform larvae. The infectious larvae penetrate intact skin, often through bare feet, and migrate through the bloodstream to the lungs, are coughed up, swallowed, and reach the small intestine, where they mature into adults and produce eggs. Transmission remains largely environmental, and good sanitation and footwear reduce risk.

Clinical features

Intestinal Ancylostoma infections can cause iron-deficiency anemia, abdominal pain, diarrhea, and malnutrition, especially in children and with heavy worm burdens. In humans, some species cause cutaneous larva migrans, characterized by intensely pruritic, serpentiginous tracks resulting from larvae migrating within the skin, most commonly due to A. braziliense and A. caninum.

Diagnosis and treatment

Diagnosis typically relies on stool examination for parasite eggs; species identification may require larval or adult morphology or molecular methods. Treatments include anthelmintics such as albendazole or mebendazole, with pyrantel pamoate as an alternative. Iron supplementation may be needed for anemia.

Prevention

Prevention focuses on sanitation, wearing shoes to prevent skin penetration, and controlling infections in domestic animals through regular deworming and proper fecal management.