Global Polio Vaccination Research in the Eradication Endgame

Polio vaccination has been instrumental in global public health, bringing the world closer than ever to eradicating a once-devastating disease. Yet the eradication endgame has become increasingly complex due to vaccine-derived polioviruses, immunity gaps, geopolitical instability, surveillance challenges, and persistent inequities in health systems and research capacity. To date, a comprehensive and methodologically integrated bibliometric analysis of global polio vaccination research has been lacking. This study provides a comprehensive analysis of global polio vaccination research published between 1956 and 2024 to examine the changing scientific, surveillance, governance, and policy priorities shaping the final phase of global polio eradication. A total of 465 peer-reviewed articles indexed in the Web of Science were analyzed using Bibliometrix, VOSviewer, CiteSpace, and Stata. Reference Publication Year Spectroscopy, co-occurrence, co-citation, bibliographic coupling, collaboration network, and thematic evolution analyses were performed to map the intellectual structure, historical development, institutional leadership, and global distribution of research activity. The findings indicate sustained growth in polio vaccination research since the 1950s, with significant acceleration after the launch of the Global Polio Eradication Initiative in 1988. Early research focused on vaccine development, immunogenicity, and mass immunization strategies, whereas recent research articles emphasizes vaccine-derived poliovirus (VDPV) management, outbreak response, surveillance innovation, and health equity. Although the transition from oral polio vaccines to inactivated polio vaccines has reduced VDPV risk, persistent immunity gaps, vaccine hesitancy, political instability, and structural inequities continue to challenge eradication efforts. Emerging themes include next-generation oral vaccines, AI-enabled surveillance systems, and post-polio syndrome rehabilitation. Despite major scientific advances, substantial geographic and economic inequalities persist, with high-income countries dominating research output and institutional leadership, while endemic and high-risk regions remain underrepresented within global research networks. These findings highlight the need for equitable research investment, stronger participation of endemic regions, resilient surveillance systems, and sustained international collaboration to support context-sensitive eradication strategies and future infectious disease preparedness.