Howard Markel, MD, PhD (ANN ARBOR, MI), is the George E. Wantz Distinguished Professor of the History of Medicine and the director of the Center for the History of Medicine at the University of Michigan. He is the author of numerous books, including The Secret of Life: Rosalind Franklin, James Watson, Francis Crick, and the Discovery of DNA's Double Helix and When Germs Travel: Six Major Epidemics That Have Invaded America and the Fears They Have Unleashed.