Toxocariasis in sibs.

Toxocariasis is caused by larva of the nematode Toxocara canis or catis. It has been found in a survey that in Southern England about 20% of dogs and cats are infected by the parasite (Woodruff, Thacker, and Shah, 1964). Man becomes infected by ingesting eggs which develop into larvae in his gastro-intestinal tract and then penetrate through the wall invading various organs in the body, most commonly the liver, lungs, and eyes. But any organ can be involved. The parasite usually persists in the larval stage in man, and can remain alive for a year or longer (Dent, Nichols, Beaver, Carrera, and Staggers, 1956). The lesions formed are of a granulomatous nature and consist of eosinophils, giant cells, and lymphocytes, which typically surround larvae and may lead to necrotic changes. Two cases in sibs are described. It is suggested that the disease is much more common than is generally believed and, though it may run a benign course with full recovery, it seems, judging from the many reports of serious ocular manifestations (Ashton, 1960), that it should be treated as a potentially serious disease.