1. Department of Pathology, University of Washington, Seattle, United States
2. Vaccine and Infectious Disease Division, Fred Hutchinson Cancer Research Center, Seattle, United States
3. Department of Environmental and Occupational Health Sciences, University of Washington, Seattle, United States
4. Department of Biostatistics, University of Washington, Seattle, United States
5. Department of Veterinary Pathobiology, University of Missouri, Columbia, United States
6. Department of Comparative Medicine, University of Washington, Seattle, United States