Toxocariasis is caused by a series of related nematode species (ascarids) that routinely infect dogs and cats throughout the world. The eggs from these ascarids are common environmental contaminants of human habitation, due largely to the fact that many kinds of dogs and cats serve as pets.Human toxocariasis is caused by migration of the larvae of Toxocara canis (dog roundworm) and less frequently of T. cati (cat roundworm) through the human tissues. Toxocara are nematode parasites of animals.
Albendazole is the treatment of choice for toxocariasis. Patients receiving a 5-day treatment course of albendazole (10 mg/kg of body weight/day in two divided doses) improved relative to patients who received treatment with the older anthelminthic drug thiabendazole .In the Switzerland, about 273 cases of Toxocara infection are reported in humans each year. Almost 10% of the Switzerland population is infected with Toxocara, a parasite of dogs and cats that can be passed from animals to humans.