Zika virus (ZIKV) epidemic now involves 72 countries, worldwide. Transmission is multimodal through mosquito bites and blood and body fluids. Zika virus causes Guillain-Barre Syndrome and pregnancy complications including perinatal microcephaly. Diagnosis is complicated by subclinical infection in 80%, co-circulation with dengue and chikungunya fevers with similar presentations and cross-reactivity in serological tests. There is no cure, or preventive vaccine. Large population-based studies will help to elucidate ZIKV epidemiology, vertical transmission, risks to the fetus of maternal ZIKV infection and natural history of congenital and non-congenital ZIKV infection as provided by the activities in the “ZIKAction” research consortium in Latin America, Europe and the Caribbean, which was recently funded by the European Commission.