Epidemiology of Viral Infections

Epidemiology is the study of the distribution, the dynamics, and the determinants of diseases in populations. The risk of virus infection and/or clinical disease is determined by characteristics both of the virus, and the levels of innate and acquired resistance in the community. Virus transmission is affected by behavioral, environmental, and ecological factors. Knowledge of these factors contributes to evidence-based policy decisions as to how best to control and prevent virus diseases. Considerable use of genome sequencing of isolates now provides useful information as to the identification of outbreak sources as well as informing the design and testing of candidate vaccines.