Interplay between cost and benefits triggers nontrivial vaccination uptake

TL;DR

This paper presents a mathematical model of vaccination behavior that reveals a non-monotonic relationship between vaccine coverage and vaccine imperfection, highlighting complex dynamics in epidemic control.

Contribution

It introduces a solvable mean-field model capturing the interplay between vaccine efficacy and uptake, explaining counterintuitive vaccination patterns.

Findings

Vaccination coverage can decrease as vaccine imperfection increases.

The model's predictions align with extensive Monte Carlo simulations.

Non-monotonic vaccination behavior is explained through stability analysis.

Abstract

The containment of epidemic spreading is a major challenge in science. Vaccination, whenever available, is the best way to prevent the spreading, because it eventually immunizes individuals. However, vaccines are not perfect, and total immunization is not guaranteed. Imperfect immunization has driven the emergence of anti-vaccine movements that totally alter the predictions about the epidemic incidence. Here, we propose a mathematically solvable mean-field vaccination model to mimic the spontaneous adoption of vaccines against influenza-like diseases, and the expected epidemic incidence. The results are in agreement with extensive Monte Carlo simulations of the epidemics and vaccination co-evolutionary processes. Interestingly, the results reveal a non-monotonic behavior on the vaccination coverage, that increases with the imperfection of the vaccine and after decreases. This apparent counterintuitive behavior is analyzed and understood from stability principles of the proposed mathematical model.