A new model to study on physical behaviour among susceptible infective removal population

This paper is concerned about developing a susceptible-infected-removed (SIR) epidemic model and to test itsâ' various effects in studying a population for evaluation of policies such as disease prevention, preparedness and response strategy to control the spread of disease. The SIR model has been divided into three disjoint groups of susceptible, infected and recovered populations and expressed by the differential equations. The theoretical solutions of these equations are determined with empirical results. Findings reveal that there exists a large class of functions representing interaction between susceptible and infective populations for which the model shows a very realistic behaviour. The rate of change of removal population follows a fairly skewed t-distribution pattern with a very rapid increase to the peak, but a slightly slower decreasing trend toward the right. An application of the model is also offered to assess the control of typhoid epidemic by vaccination.