Epidemiology of neurocysticercosis in Houston, Texas

We identified 114 patients with neurocysticercosis admitted to Ben Taub General Hospital in Houston, Texas between January 1994 and June 1997. Most of these patients were born in Mexico (78%) or Central America (16%), but 6% were born in the United States. Review of neurology clinic records identified 54 patients diagnosed with neurocysticercosis, representing 2% of all neurology clinic patients and 16% of all Hispanics diagnosed with seizures. Forty-one patients were interviewed and all reported significant risk factors for infection, including ingestion of undercooked pork, pig husbandry, immigration from and frequent travel to villages in disease-endemic areas, or personal/family history of taeniasis. Among Mexican immigrants, most were born in rural areas in Central (31%) or north central Mexico (38%). Significantly fewer of the patients were from the border states (15%). The median period from immigration to diagnosis was 58 months, but it was 28 months for the 13 patients who had not left the United States after immigration. Although neurocysticercosis is being diagnosed with increasing frequency in the United States, acquisition of infection is still strongly associated with pig husbandry in rural Latin America, with little evidence of local transmission. Even among urban immigrants to the United States and United States-born cases, there is close ongoing contact with disease-endemic villages.