1. International Vaccine Access Center, Johns Hopkins University , 415 N Washington St. 5th floor, Baltimore, MD 21231, USA
2. Jhpiego, a Johns Hopkins University Affiliate , 1615 Thames St. # 200, Baltimore, MD 21231, USA
3. School of Nursing, Johns Hopkins University , 525 N. Wolfe St., Baltimore, MD 21205, USA
4. Center for Health Security, Johns Hopkins Bloomberg School of Public Health , 621 E. Pratt St., Baltimore, MD 21201, USA
5. Center for the Evaluation of Vaccination, University of Antwerp , Drie Eikenstraat 663, Antwerp, Edegem 2650, Belgium
6. Department of International Health, Johns Hopkins Bloomberg School of Public Health , 615 N. Wolfe St. Suite E8527, Baltimore, MD 21205, USA