Respiratory syncytial virus (RSV) vaccines protect against a virus that infects an estimated 64 million people and causes 160,000 deaths globally each year. Several vaccines are now approved, including Arexvy (GSK), Abrysvo (Pfizer), and Mresvia (Moderna), with Abrysvo also approved for pregnant individuals to protect their infants. In June 2024, the CDC updated its guidance, recommending the vaccine for everyone aged 75 and older, and for those aged 60–74 with chronic conditions like lung or heart disease. The path to these vaccines was rocky: a 1960s formalin-inactivated vaccine caused severe enhanced disease and two deaths, stalling research for decades. A pivotal 2013 study detailing the structure of the RSV fusion (F) protein paved the way for the 2023 approvals and even accelerated COVID-19 vaccine development. Today, the RSV vaccine is listed on the World Health Organization's List of Essential Medicines.