The present invention is related to the field of the pharmaceutical industry, and describes a conserved area on the surface of the E protein that can be used for the development of wide-spectrum antiviral molecules to be employed in the prophylaxis and/or treatment of infections due to Dengue Virus serotypes 1-4 and other flaviviruses. The invention also covers chimeric proteins to be used as vaccines or as a prophylactic or therapeutic treatment against the four serotypes of Dengue Virus and other flaviviruses.