Live life or die trying? The balance between being social & staying healthy during epidemics.

Synopsis by Kezia Manlove

During an epidemic, an individual risks becoming infected every time they come into contact with somebody who’s sick. Individuals should, therefore, embrace behaviors that increase their distance from others. However, behavioral changes are costly and it can be difficult to identify the best way to behave. This task is made particularly difficult when behavioral changes of individuals alter the dynamics of the epidemic and, in turn, change which behavioral strategy is best. Traditional models of disease dynamics often fail to capture this feedback and tend to model epidemic control strategies, like behavioral modification, as operating upon individuals rather than being taken up by them by choice. In a recent paper published in Bulletin of Mathematical Biology, CIDD Researcher & Bellman Prize Recipient Tim Reluga uses a game theoretic approach to explicitly model the drivers shaping an individual's decision to participate in a behavioral mitigation strategy.

Reluga provides an analytical solution to a model in which individuals during an epidemic invest in behaviors in such a way as to balance the costs of prevention against the costs of infection. Importantly, he shows that there is only one way to do this that satisfies everybody. His results can be used to determine where the cost-benefit trade-off of distancing oneself from others may play an important role in disease dynamics. Reluga's flexible numerical protocol represents a powerful new framework with which to investigate the efficacy of various disease control strategies like vaccination in the context of many different diseases. This research adds rigor to a growing body of work aimed at understanding efforts to control disease from a game-theoretic perspective and offers new insights into how the decisions of individuals can influence disease transmission during epidemics.