1. From the Foodborne and Diarrheal Diseases Branch, Division of Bacterial and Mycotic Diseases (Angulo), Parasitic Diseases Branch, Division of Parasitic Diseases (Juranek), and Viral and Rickettsial Zoonoses Branch, Division of Viral and Rickettsial Diseases (Regnery), National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333; the Center for AIDS Prevention Studies, Pediatric Infectious Diseases, University of California, San Francisco...