1. Antibiotic Resistance Monitoring and Reference Laboratory, Specialist and Reference Microbiology Division—Colindale, Health Protection Agency, London, United Kingdom
2. Departments of Microbiology & Pathology, Tisch Hospital, NYU Medical Center
3. Human and Animal Infectious Disease Research, Merck Research Laboratories, Rahway, New Jersey
4. New York City Department of Health, Public Health Laboratory, New York, New York