Dengue has created havoc across the country. With many people suffering with this life-threatening disease timely diagnosis and intervention is the need of the hour. You will also be shocked to know that people who do not exhibit any symptoms can also be a medium of the danger disease. People who virtually show no symptoms are likely to be the primary source of dengue fever according to a new study. 80% of dengue virus infections are spread through individuals with mild to no symptoms. About 400 million people each year are infected with dengue virus which is transmitted by mosquitoes.