Abstract
1 Laboratory of Clinical Virology, Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
2 Laboratory of Experimental Virology, Department of Medical Microbiology, Academic Medical Center, Amsterdam, The Netherlands
3 Department of Biological Sciences, University of Essex, Colchester CO4 3SQ, UK
4 Virus Evolution Group, Centre for Infectious Diseases, University of Edinburgh, Edinburgh EH9 1AJ, UK