1. Division of Infectious Diseases, Mayo Clinic, Rochester, Minnesota, USA
2. Division of Infectious Diseases, University of Minnesota, Minneapolis, Minnesota, USA
3. HIV Program, Hennepin County Medical Center, Minneapolis, Minnesota, USA
4. Department of Laboratory Medicine and Therapeutic Pathology, University of Pennsylvania, Philadelphia, Pennsylvania, USA
5. Department of Biostatistics, Mayo Clinic, Rochester, Minnesota, USA
6. Department of Biochemistry and Molecular Biology, Mayo Clinic, Rochester, Minnesota, USA
7. Department of Molecular Medicine, Mayo Clinic, Rochester, Minnesota, USA