The path to equitable respiratory syncytial virus prevention for infants: challenges and opportunities for global implementation.

The approval for a respiratory syncytial virus (RSV) maternal vaccination programme by Gavi, The Vaccine Alliance, marks substantial progress toward equitable access, with important work still to come. Several countries, most of which are high-income, have introduced RSV immunisation either using a vaccine containing the RSV fusion protein in its prefusion conformation, which is given to pregnant people in late pregnancy, or by using a long-acting monoclonal antibody (mAb) administered directly to infants. Post-implementation real-world effectiveness data show a major impact in reducing medically attended RSV-lower respiratory tract illness and hospitalisation using either strategy. Although RSV poses a substantial burden to infants and vulnerable children worldwide, 97% of associated mortality occurs in low-income and middle-income countries. However, few of these countries have authorised and introduced RSV preventive strategies. This Review outlines the challenges and opportunities for expanding access to RSV prevention for infants in resource-restricted settings guided by WHO's Immunization Agenda 2030 and the UN's Leave No One Behind framework for non-discriminatory sustainable development. We discuss burden, vaccine and mAb development, health economics and impact modelling, policy, implementation and programmatic considerations, surveillance, and awareness as key RSV domains. This Review summarises recent advances in research and highlights the urgent steps needed to ensure equitable access to RSV prevention for all infants worldwide.