1 Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan; Global Institute for Vaccine Equity, University of Michigan, Ann Arbor, Michigan; Infectious Disease Division, Department of Internal Medicine, Michigan Medicine, Ann Arbor, Michigan. Electronic address: mboulton@umich.edu.
2 Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, Michigan; Global Institute for Vaccine Equity, University of Michigan, Ann Arbor, Michigan.