About the Authors

Edward C. Holmes

ech15@psu.edu

Affiliations Center for Infectious Disease Dynamics, Department of Biology, The Pennsylvania State University, Mueller Laboratory, University Park, Pennsylvania, United States of America, Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America

Bryan T. Grenfell

Affiliations Fogarty International Center, National Institutes of Health, Bethesda, Maryland, United States of America, Department of Ecology and Evolutionary Biology and Woodrow Wilson School, Princeton University, Princeton, New Jersey, United States of America

Competing Interests

The authors have declared that no competing interests exist.