1. Department of Global Public Health, Karolinska Institutet, Tomtebodavägen 18B, 17165 Solna, Sweden.
2. Department of Economics, Finance and Statistics, Jönköping International Business School, JönköpingSweden.
3. FOCUS1000, Freetown, Sierra Leone.
4. Division of Global Health Protection, US Centers for Disease Control and Prevention, Atlanta, United States of America.