Measures to asses an optimal vaccination coverage in a stochastic SIV model with imperfect vaccine

This communication is framed within the area of epidemic modelling in a stochastic approach. An additional compartment of vaccinated individuals is considered in a stochastic SIS model within a not isolated, homogeneous, and uniformly mixed population. The vaccine is not 100% effective and individuals are partially protected against the disease. The propagation of a contagious disease is modelled in terms of a continuous time Markov chain where individuals evolve among susceptible, S, vaccinated, V, and infected, I; compartments.A well-known measure of the initial transmission potential is the basic reproduction number R_0, which determines the herd immunity threshold or the critical proportion of immune individuals required to stop the spread of a disease when a vaccine offers a complete protection. Assuming that the vaccine is imperfect, alternative measures to R_0 are defined in order to study the influence of the initial coverage on the transmission of the epidemic. The talk is based on the paper: Gamboa, M., and Lopez-Herrero, M. J. (2020). Measuring infection transmission in a stochastic SIV model with infection reintroduction and imperfect vaccine. Acta biotheoretica, 1-26.https://doi.org/10.1007/s10441-019-09373-9.