Virus evolution current research and future directions / edited by Scott C. Weaver, Institute for Human Infections and Immunity and Departments of Pathology, Microbiology & Immunology, Galveston, TX, USA, Mark Denison, Division Infectious Diseases, Vanderbilt University School Medicine, Nashville, TN, USA, Marilyn Roossinck, Center for Infectious Disease Dynamics, The Pennsylvania State University, University Park, PA, USA, and Marco Vignuzzi, Viral Populations and Pathogenesis Group, Pasteur Institut, Paris, France.