In neurocysticercosis, which parasite stage migrates to the brain to form cysts after eggs are ingested into the bloodstream?

• A. Adults
• B. Eggs
• C. Larvae
• D. Cysts

Answer: (C)

The key idea is understanding the parasite’s life cycle and how the brain gets involved. In neurocysticercosis, the brain is infected by the larval form after eggs are ingested. Those eggs hatch in the gut and release larvae (oncospheres), which penetrate the intestinal wall and spread through the bloodstream to various tissues, including the brain. There, they develop into cysticerci, which are cystic larvae. So the migrating stage that travels to the brain is the larval form. The adults stay in the intestine, eggs are just the transmitted stage, and cysts are the final tissue lesions formed after the larvae settle in the brain.