1 International Vaccine Access Center, Department of International Health, Bloomberg School of Public Health, Johns Hopkins University, MD, USA. Electronic address: nbarzee1@jhu.edu.
2 Malaria Epidemiology Research Group, Malawi Liverpool Wellcome Research Programme, Blantyre, Malawi; Department of Clinical Infection, Microbiology & Immunology, Institute of Infection, Veterinary and Ecological Sciences, University of Liverpool, Liverpool, UK; Department of Public Health, School of Global and Public Health, Kamuzu University of Health Sciences, Blantyre, Malawi.