Pre-emptive Vaccination Versus Late Vaccination

Abstract

AbstractThe conventional vaccination game always assumed pre-emptive vaccination, by which an individual decides whether or not to participate in a vaccination game prior to an epidemic season. This chapter develops a new vaccination-game framework where not only pre-emptive vaccination but also late vaccination is available, which is more realistic. The two-layer vaccinating opportunity allows the coevolution of individual behavior around vaccination to avoid infection. Based on the potential risk of infection that is influenced by how many people vaccinate while being infected, late vaccination allows an individual who is not taking a pre-emptive vaccination to participate in a literally “late-timed vaccination” at any arbitrary moment in an epidemic season. The theoretical model presented in this chapter is validated by the results obtained through multi-agent simulation (MAS). Furthermore, this chapter quantitatively demonstrates that the cost advantage of late vaccination over pre-emptive vaccination enables an individual to prefer late vaccination, and lower vaccine effectiveness compels an individual who previously intended to free ride to choose late vaccination.