Cysticercosis is an infection caused by the pork tapeworm, Taenia solium. Infection occurs when the tapeworm larvae enter the body and form cysticerci.
When cysticerci are found in the brain, the condition is called neurocysticercosis
The tapeworm that causes cysticercosis is found worldwide. Infection is found most often in rural, developing countries with poor hygiene where pigs are allowed to roam freely and eat human feces. This allows the tapeworm infection to be completed and the cycle to continue.
Infection can occur, though rarely, if you have never traveled outside of the United States. Taeniasis and cysticercosis are very rare in Muslim countries where eating pork is forbidden.