1. Division of Infectious Diseases, Department of Medicine, Duke University School of Medicine , Durham, North Carolina , USA
2. Department of Laboratory Medicine and Pathology, University of Washington , Seattle, Washington , USA
3. Division of Allergy and Infectious Diseases, Department of Medicine, University of Washington , Seattle, Washington , USA
4. Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Center , Seattle, Washington , USA
5. Clinical Research Division, Fred Hutchinson Cancer Center , Seattle, Washington , USA