1. Division of Infectious Diseases, Department of Medicine, Stanford University
2. Department of Internal Medicine, Kaiser Permanente Northern California, San Francisco
3. Department of Infectious Diseases, Kaiser Permanente Northern California, San Leandro
4. Department of Infectious Diseases, Kaiser Permanente Northern California, Oakland
5. Department of Pathology, Stanford University, California
6. Harvard Medical School and Harvard Pilgrim Health Care Institute, Boston, Massachusetts
7. Division of Research, Kaiser Permanente Northern California, Oakland
8. Department of Biology, Temple University, Philadelphia, Pennsylvania