The Yellow Fever Vaccine Journey: Milestones and Future Directions.

Yellow fever, a mosquito-borne viral hemorrhagic disease, remains a significant public health concern in endemic regions of Africa and South America. The development of the yellow fever vaccine marked a milestone in virology and immunization. In the 1930s, Max Theiler created the 17D live-attenuated vaccine, a breakthrough that has achieved global recognition and continues to underpin prevention strategies. This review outlines the historical evolution of the yellow fever vaccine, highlighting pivotal scientific advances, technological innovations, and global eradication initiatives. It examines the current landscape of immunization, focusing on the World Health Organization's Eliminate Yellow Fever Epidemics (EYE) strategy, ongoing efforts to address vaccine supply constraints, and persistent surveillance gaps. Future directions in vaccine development, including next-generation platforms and improved delivery systems, are also discussed, alongside the need for sustained research investment and international collaboration. As yellow fever emerges in previously non-endemic areas due to climate change and globalization, strengthening vaccination programs remains critical to preventing outbreaks and ensuring effective disease control.