ABSTRACT
The COVID-19 pandemic has spread widely through the world, since 2019. Then, the search for vaccines has become fundamental against the disease and has generated great expectations on population. In Brazil, the first case of COVID-19 was registered in February 2020 and the process of vaccination started in early 2021. In this context, considering the advance of vaccination and the behavior of epidemics, we present a study on the effect of population-wide vaccination on the evolution of the COVID-19 epidemic. To this end, we propose a new fuzzy system in order to model the COVID-19 epidemic evolution under the effect of vaccination in Brazil. This proposed model consists of a p-fuzzy system, where the input variables are the infected population and the vaccination rate. The output variable is the level of infection. Results of the proposed fuzzy system show that the level of infestation tends to decrease as the number of people vaccinated increases. Therefore, the population-wide vaccination strategy clearly contributes to suppressing the growth of the disease and to mitigating its impacts on society, including saving lives.