Effect of immigration on disease spread: a SEI model

An SEI model with constant immigration and standard incidence function is investigated. In this age, immigration is a common activity that happens due to various reasons. Unfortunately, immigration can become one of a reason for infectious diseases to spread globally. In order to investigate the impact of immigration on the disease spread, the SEI model is applied. Using the TB disease as an example, the model is solved numerically using the Runge-Kutta method of order 4 (RK4). The results are presented graphically and in tabular form. The effect of immigration does not seem crucial initially on the TB disease spread but will have an impact on the population that is noticeable as time goes by. Compared to the immigration parameter, another parameter has a bigger impact on our model. It is discovered that a higher contact rate with infectious people will outweigh the effect of immigration. An action plan has been presented where we have to determine who is highly potential to spread the disease and isolate them to control the disease from entering the country through immigration