CHARLES CALISHER, Ph.D., was at the U.S. Centers for Disease Control in Atlanta, Georgia, and Fort Collins, Colorado for 27 years as Chief of the Arbovirus Reference Branch and Director of the World Health Organization Collaborating Centre for Arboviruses in the Americas. He is now Professor Emeritus, Arthropod-borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, and a member of the Columbia University, Center for Infection and Immunity, Mailman School of