Science
10 July 2009  Vol 325, Issue 5937, Pages 117-232

http://www.sciencemag.org/current.dtl

Research Articles
Demographic Variability, Vaccination, and the Spatiotemporal Dynamics of Rotavirus Epidemics

Virginia E. Pitzer,1,2,* Cécile Viboud,2 Lone Simonsen,3 Claudia Steiner,4 Catherine A. Panozzo,5 Wladimir J. Alonso,2 Mark A. Miller,2 Roger I. Glass,2 John W. Glasser,5 Umesh D. Parashar,5 Bryan T. Grenfell1,2,6

Historically, annual rotavirus activity in the United States has started in the southwest in late fall and ended in the northeast 3 months later; this trend has diminished in recent years. Traveling waves of infection or local environmental drivers cannot account for these patterns. A transmission model calibrated against epidemiological data shows that spatiotemporal variation in birth rate can explain the timing of rotavirus epidemics. The recent large-scale introduction of rotavirus vaccination provides a natural experiment to further test the impact of susceptible recruitment on disease dynamics. The model predicts a pattern of reduced and lagged epidemics postvaccination, closely matching the observed dynamics. Armed with this validated model, we explore the relative importance of direct and indirect protection, a key issue in determining the worldwide benefits of vaccination.

1 Center for Infectious Disease Dynamics, Pennsylvania State University, State College, PA 16801, USA.
2 Fogarty International Center, National Institutes of Health, Bethesda, MD 20892, USA.
3 School of Public Health and Health Services, George Washington University, Washington, DC 20052, USA.
4 Healthcare Cost and Utilization Project, Center for Delivery, Organization and Markets, Agency for Healthcare Research and Quality, U.S. Department of Health and Human Services, Rockville, MD 20850, USA.
5 Epidemiology Branch, Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, GA 30333, USA.
6 Department of Ecology and Evolutionary Biology and Woodrow Wilson School, Princeton University, Princeton, NJ 08544, USA.