1. Institute of Virology, University Clinics and Faculty of Medicine, University of Leipzig, Leipzig, Germany.
2. Department of Microbiology, Faculty of Sciences, International University of Africa, Khartoum, Sudan.
3. Department of Medical Entomology, National Health Laboratory, Khartoum, Sudan.
4. Department of Virology, Paul-Ehrlich-Institut, Langen, Germany.
5. Bernhard Nocht Institute for Tropical Medicine, WHO Collaborating Centre for Arbovirus and Haemorrhagic Fever Reference and WHO Collaborating Research Centre, Hamburg, Germany.
6. Friedrich-Loeffler-Institut, Insel Riems, Germany.