In particular, the aim is to define the epitope breadth/repertoire and the targets of CD4 and CD8 responses; to derive sets of HLA class I and class II predicted epitopes covering the entire ZIKV proteome; to define phenotypes and T-cell subsets associated with CD4 and CD8 specific T cells; to identify the major type-specific and crossreactive B-cell epitopes on ZIKV, and to assess the role of flavivirus antibodies in protective and pathogenic immunity (e.g. related to prior dengue infections, dengue, and yellow fever vaccines). Here, CD4 is linked to viral infectious disease.