1. Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
2. Department of Public Health and Community Medicine, School of Medicine, Tufts University, Boston, MA 02111, USA
3. Department of Epidemiology, Rollins School of Public Health, Emory University, Atlanta, GA 30322, USA
4. Emory Vaccine Center, Emory University, Atlanta, GA 30322, USA
5. Department of Civil and Environmental Engineering, School of Engineering, Tufts University, Medford, MA 02155, USA