Zoonotic toxocariasis (visceral larva migrans or VLM & ocular larva migrans or OLM) refers
to human infection caused by helminths that are not natural human parasites. Toxocariasis is an
underestimated geohelminthic infection may be worldwide.
Toxocariasis occurs as a result of human infection with the dog ascarid larvae, Toxocara canis
or less commonly, the cat ascarid larvae, T. cati. VLM is mainly a disease of young children,
especially those with exposure to playgrounds and sandboxes contaminated by dog or cat
feces. While common globally, prevalence in both animals and people is highest in developing
countries. In developed countries, more infections are detected among persons in lower socioeconomic
strata. TVLM & OLM clinical presentations, although most infections are asymptomatic,
yet in VLM, which occurs mostly in preschool children, larvae invade multiple tissues
(mainly liver, lung, skeletal muscle, or heart) causing nonspecific symptoms as fever, myalgia,
weight loss, cough, rashes, hepatosplenomegaly accompanied by hypereosinophilia. Migration
to CNS (neurotoxocariasis) is uncommon and can cause eosinophilic meningoencephalitis and
epilepsy. Death can occur with severe cardiac, pulmonary, or neurologic involvement.