1 Department of Tropical Medicine, Bernhard Nocht Institute for Tropical Medicine and I. Department of Medicine, University Medical Center Hamburg-Eppendorf, Hamburg, Germany.
2 Institut für Tropenmedizin, Universität Tübingen, Tübingen, Germany.
3 Centre de Recherches Médicales de Lambaréné, Lambaréné, Gabon.
4 German Center for Infection Research (DZIF), partner site Hamburg-Luebeck-Borstel, Hamburg, Germany.