Flexible imitation suppresses epidemics through better vaccination

TL;DR

This paper presents a minimalistic model showing that flexible decision-making in vaccination, based on social influence and learning from experience, can enhance vaccine uptake and reduce epidemic severity.

Contribution

It introduces a novel model combining game theory, network theory, and epidemic modeling to study adaptive vaccination decisions based on social neighborhood responses.

Findings

Flexibility in decision strategies increases vaccination rates.

Longer memory of past outbreaks improves epidemic control.

Limited initial imitation promotes better vaccination outcomes.

Abstract

The decision of whether or not to vaccinate is a complex one. It involves the contribution both to a social good -- herd immunity -- and to one's own well being. It is informed by social influence, personal experience, education, and mass media. In our work, we investigate a situation in which individuals make their choice based on how social neighbourhood responded to previous epidemics. We do this by proposing a minimalistic model using components from game theory, network theory and the modelling of epidemic spreading, and opinion dynamics. Individuals can use the information about the neighbourhood in two ways -- either they follow the majority or the best-performing neighbour. Furthermore, we let individuals learn which of these two decision-making strategies to follow from their experience. Our results show that the flexibility of individuals to chose how to integrate information from the neighbourhood increases the vaccine uptake and decreases the epidemic severity if the following conditions are fulfilled. First, the initial fraction of individuals who imitate the neighbourhood majority should be limited, and second, the memory of previous outbreaks should be sufficiently long. These results have implications for the acceptance of novel vaccines and raising awareness about vaccination, while also pointing to promising future research directions.