1 Institute of Global Health, Faculty of Medicine, University of Geneva, CH-1202 Geneva, Switzerland.
2 Institute of Economics and Econometrics, GSEM, University of Geneva, Geneva, Switzerland.
3 HEC, University of Lausanne, Lausanne, Switzerland.
4 Institute of Global Health, Faculty of Medicine, University of Geneva, CH-1202 Geneva, Switzerland; Centre Virchow-Villermé, University Paris Descartes, Paris, France. Electronic address: antoine.flahault@unige.ch.