There was a time when Renaldo Ramirez, of Houston, didn't like to cook. The 50-year-old ate most of his meals at mobile kitchens until he found out food contaminated with tapeworm eggs almost killed him. "He's scared now. He's scared of any food from outside," Ramirez said through his sister who interpreted for him. Ramirez is a tile worker who immigrated to the U.S. from El Salvador 20 years ago. "It was a mild headache, but it wouldn't go away," he said. "It was just there and it wouldn't go away with Tylenol." Doctors at a clinic gave him medicine...