1. Department of Epidemiology, University of Washington , Seattle, Washington , USA
2. Department of Medicine, Division of Allergy and Infectious Diseases, University of Washington , Seattle, Washington , USA
3. Neisseria Reference Laboratory, University of Washington , Seattle, Washington , USA
4. Department of Global Health, University of Washington , Seattle, Washington , USA
5. Department of Biostatistics, University of Washington , Seattle, Washington , USA
6. HIV/STD Program, Public Health–Seattle and King County , Seattle, Washington , USA
7. Department of Medicine, University of Washington , Seattle, Washington , USA