Another study demonstrated that DENV/ZIKV co-infection decreased the ability of CD4+ T cells to produce IFN-γ+ and TNF+ compared to single DENV and ZIKV infections, showing the lack of cross-reactivity between DENV and ZIKV specifically CD4+ cells for envelope and NS1 proteins [17,121]. Here, CD4 is linked to Zika virus infectious disease.