Toxocara canis and Toxocara cati eggs are shed in the stool of the definitive host (dog or cat respectively) and may be accidentally ingested by a human. Each egg then hatches to release a larva which migrates throughout the human body causing visceral larva migrans. The larvae cannot mature in humans, and humans are therefore dead-end hosts. Eggs are not seen in human stool specimens, but may be seen in soil that is contaminated with the feces of an infected dog or cat.