1. Preventive Medicine & Biometrics Department; Uniformed Services University of the Health Sciences; 4301 Jones Bridge Rd. Bethesda MD 20814-5119
2. Enteric Diseases Program, Naval Medical Research Center; 503 Robert Grant Ave. Silver Spring MD 20910-7500
3. Department of Biochemistry and Molecular Biology; Medical College of Georgia; 1120 15th St. Augusta GA 30912-2100