Therapeutic battle against larval toxocariasis: Are we still far behind?

Toxocara infection is a widespread zoonotic disease. It causes several distinct clinical features. Its treatment is a matter of clinical and laboratory judgement. [Display omitted] ► Treatment of toxocariasis is a matter of clinical and laboratory judgement. ► Experimental treatment trials provide a model for therapy, but several precautions are to be in mind. ► Human trials are needed as well as standardization of therapeutic indications and criteria of cure. Toxocariasis is a widespread zoonotic helminthic disease. Human infection is acquired by ingestion of embryonated eggs of Toxocara which reach the environment via stools of dogs and cats. In paratenic hosts, such as humans and mice, the hatched larvae migrate systematically in the body and could reach critical sites such as the eye and the central nervous system. The clinical expression of toxocariasis includes two main forms of varying intensity: visceral and ocular, as well as several organ-specific clinical manifestations. The issue of treatment is a matter of great controversy not only because of limited efficacy of anthelmintic drugs in terms of parasite eradication, but also because of doubts about the benefits of therapy as most Toxocara infections are self-limiting. Many animal studies were conducted employing different drugs and regimens, yet the results were variable and inconsistent. On the other hand, experience in human therapy is unfortunately limited due to paucity of clinical trials. Herein, the problems and pitfalls of treatment of toxocariasis are addressed, and new trends in therapy are discussed.