Fred Brauer is a professor emeritus at the University of Wisconsin - Madison, where he taught from 1960 to 1999, and has been an honorary professor at the University of British Columbia since 1997. He is the author or co-author of 115 papers on differential equations, mathematical population biology, and mathematical epidemiology as well as 10 books including undergraduate texts and a book on models in population biology and epidemiology jointly with Carlos Castillo - Chavez. Pauline van den Driessche is a professor emerita in the Department of Mathematics and Statistics and an adjunct professor in the Department of Computer Science at the University of Victoria. Her research interests include mathematical biology, especially epidemiology, and matrix analysis. Recently she was awarded the 2007 Krieger - Nelson prize by the Canadian Mathematical Society, and gave the Olga Taussky Todd lecture at the International Conference in Industrial and Applied Mathematics in July 2007. Jianhong Wu is a professor and a Senior Canada Research Chair in Applied Mathematics at York University. He is the author or coauthor of over 200 peer-reviewed publications and six monographs in the areas of nonlinear dynamical systems, delay differential equations, mathematical biology and epidemiology, neural networks, and pattern formation and recognition. He is the recipient of the Canadian Industrial and Applied Mathematics Research Prize (2003), the Alexander van Humboldt Fellowship (1996), the Paul Erdos Visiting Professorship (2000), and Cheung Kong/YangZi River Lecture Professorship (2006).