The purpose of EBOVAC 2 study is to assess the safety, tolerability and immunogenicity of three heterologous prime-boost regimens for Ebola vaccines Ad26.ZEBOV and MVA-BN-Filo. The study includes healthy adults and elderly participants, HIV infected participants and healthy children in 2 age strata. EBOVAC2 has been awarded a "Star of Europe" Special Prize by the French Ministry of Research in 2021. This trophy aims at rewarding and valorizing the European commitment of the research teams which have distinguished themselves by the success of their projects.