Progress toward poliomyelitis eradication — January 2023–December 2024
TL;DR
The resurgence of WPV1 in polio-free regions in Afghanistan and Pakistan and the spread of cVDPVs challenge global polio eradication, highlighting the need for rapid detection, expanded nOPV2 use in areas with prolonged transmission, and sustained partner engagement and strategic resource allocation amid declining global health funding.
Abstract
Since the establishment of the Global Polio Eradication Initiative (GPEI) in 1988, wild poliovirus type 1 (WPV1) remains endemic in only Afghanistan and Pakistan. However, outbreaks of paralytic polio caused by circulating vaccine-derived polioviruses (cVDPVs) emerge in areas with low vaccination coverage and continue to challenge polio eradication goals. As the Global Polio Eradication Initiative extends its eradication target to 2029, understanding the epidemiologic, surveillance, and operational factors associated with persistent transmission is critical for informing policy decisions and targeting limited resources. This report describes global polio immunization efforts, surveillance activities, and epidemiology during January 2023–December 2024. Surveillance and virologic data were obtained from the World Health Organization’s (WHO) global Polio Information System (POLIS), and immunization coverage estimates were sourced from WHO’s Immunization Dashboard, which incorporates administrative and survey-based data from WHO and UNICEF. A cVDPV outbreak was defined using standardized acute flaccid paralysis (AFP) and environmental surveillance criteria; analyses were conducted in R (version 4.4.1). Afghanistan and Pakistan reported 99 WPV1 cases in 10 provinces in 2024, compared with 12 cases in 3 provinces in 2023. cVDPV cases decreased 12% from 529 in 2023 to 464 in 2024. However, cVDPV detections from AFP and environmental surveillance expanded geographically, with detections in 40 countries in Africa, Southeast Asia, the Middle East and Europe in 2024, including 14 countries with no detections in 2023. The resurgence of WPV1 in polio-free regions in Afghanistan and Pakistan and the spread of cVDPVs challenge global polio eradication. Achieving global polio eradication will require reaching persistently missed children in remote and insecure areas, strengthening vaccination and surveillance systems, and reinforcing accountability to improve campaign quality. The geographic expansion of cVDPV type 2 (cVDPV2) underscores the need for rapid detection, expanded nOPV2 use in areas with prolonged transmission, and sustained partner engagement and strategic resource allocation amid declining global health funding.