Today, the Ethics Committee of the Padua University Hospital has formally approved the ex vivo studies planned within the ZIKA-PATHO work package. Villi and primary cell lines obtained from first and second trimester and term placentas will be cultured and infected at IZSVe to evaluate the role of sub-neutralizing maternal immunity in the vertical transmission of ZIKV. The use of monoclonal antibodies isolated from patients infected with either Dengue or Zika viruses will shed a light on the possibility that prior infections might modulate the tissue tropism and pathogenicity of ZIKV infections at the level of the placenta.