Diagnosing the individual to control the epidemic

When vaccination is not an option, the only way to actively control an epidemic is to identify infectious individuals and "remove" them (by treatment, quarantine, or culling). In a recent Science paper, Charleston et al. present data and an analysis suggesting that clinical diagnosis of foot-and-mouth disease is very closely linked in time to shedding of virus; as such, removal of clinically affected animals might be sufficient to control an epidemic. Although these results are for a veterinary disease, they are very pertinent for all infectious diseases, including those of humans. In this Perspective, we consider the role of experimental research in determining the biology of infection as well as the importance of diagnosis for epidemic control.