The RNA molecular is the basis of violence and pathogenesis of Dengue hemorrhagic fever and Dengue Shock Syndrome that must to know , to ensure that dengue vaccine development overcome of dengue virus evolution. The mechanisms of vaccine-induced protection need to be clarified in future. The concurrence immunologic target of a neutralizing antibody response to all 4 serotypes in at least 80% of volunteers may not be convenient in all community and clinical settings.