Milad Taherian - Mashhad, Iran, M.Sc. Graduate Ferdowsi University of Mashhad
Behnam Bankian Tabrizi - Mashhad, Iran, M.Sc. Graduate Ferdowsi University of Mashhad
Navid Eidgah - Mashhad, Iran, M.Sc. Graduate Ferdowsi University of Mashhad

Vaccination is a vitally important measure that can be inexpensively taken in order to be protected from some contagious diseases. Today, in order to characterize contagious diseases, numerous mathematical models have been presented that are all on the basis of dividing population into separate groups. Considering the SEIRS nonlinear mathematical model for contagious diseases, an approach to optimal vaccination is presented in this paper. In the model, S is the number of people who are susceptible to the diseases, E and I are the number of infected individuals (explicit and implicit), and R is the number of people who have been fully recovered. The purpose of the paper is to decrease the value of S, E, and I and also increase the value of R considering the minimum required vaccinations. The simulation results have also been presented

Optimal control, SEIRS epidemic, model Vaccination