Cysticercosis if the person has any type of neurological problems (particularly SEIZURES) and is form Mexico/Latin America.
I mean there are tons of geographically-oriented things (Chagas Dz in South America, Arsenic in Bangladesh, etc), but I'm not sure how often those people emigrate in the question stems.
From the questions I've seen, they want you to assume either 1) that they are unvaccinated (DPT, MMR, h flu) or 2) a disease that is endemic to a certain region (stomach cancer in Japanese, nasopharyngeal carcinoma in east Asia, Burkitt's in Africa)