According to a recent article in Scientific American, a rare brain disease in the United States called "neurocysticercosis" has become an increasing issue among the Latino community in California. Neurocysticercosis is a disease which is caused by a tapeworm brain parasite. The disease is apparently most common in poorer areas that lack good health systems, as the disease is often preventable by maintaining good hygiene.
In 2009, there were 304 reported cases of neurocysticercosis in California, and allegedly $17 million was spent on treatment for the disease alone. According to Theodore Nash, who is the chief of the Gastrointestinal Parasites Section at NIH, "Nobody knows exactly how many people there are with it in the United States. Minimally there are 5 million cases of epilepsy from neurovysticercosis."
Hopefully, a vaccine will be found to eliminate this serious disease in the near future.