Abstract
Mathematics has played a substantial role to revolutionize the medicalscience. Intelligent systems based on mathematical theories have proved to beefficient in diagnosing various diseases. In this paper, we used an expertsystem based on soft set theory and fuzzy set theory named as a soft expertsystem to diagnose tropical disease dengue. The objective to use soft expertsystem is to predict the risk level of a patient having dengue fever by usinginput variables like age, TLC, SGOT, platelets count and blood pressure. Theproposed method explicitly demonstrates the exact percentage of the risk levelof dengue fever automatically circumventing for all possible (medical)imprecisions.