1. Center for Vaccine Development and Global Health, University of Maryland School of Medicine, Baltimore, Maryland, USA
2. The Institute of Genomic Sciences, University of Maryland School of Medicine, Baltimore, Maryland, USA
3. Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland, USA
4. Samoa Typhoid Fever Control Program, Ministry of Health, Apia, Samoa
5. Department of Medicine, University of Maryland School of Medicine, Baltimore, Maryland, USA
6. Department of Pediatrics, University of Maryland School of Medicine, Baltimore, Maryland, USA