The African Polio Laboratory Network: Advancing Regional Poliovirus Detection, Genomic Surveillance, and Eradication

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Background: Sustaining progress toward polio eradication requires not only effective vaccination but also a resilient laboratory network capable of timely poliovirus detection, confirmation, and genetic characterization. In the WHO African region, the African polio laboratory network provides essential virological support for eradication efforts; however, persistent circulating Vaccine-derived Polioviruses (cVDPVs) outbreaks and increasing demands of genomic surveillance continue to challenge laboratory capacity. Despite its critical role, evidence describing the operational performance, adaptive capacity, and evolution of regional polio laboratory network remains limited. This study evaluates the performance and operational experience of the African polio laboratory network in 2025, highlighting contributions to poliovirus detection, genomic surveillance, quality assurance, and outbreak response, while sharing lessons to inform regional public health systems. Methods: A retrospective secondary data analysis was conducted using laboratory surveillance and outbreak databases, supplemented by reviews of programmatic reports. Data were cleaned and harmonized prior to analysis. Descriptive analyses were performed to assess laboratory workload, timeliness indicators, genomic capacity, quality assurance performance, and operational challenges. Qualitative review of programmatic documents was conducted to identify contextual factors influencing performance. Results: In 2025, 77,230 Acute Flaccid Paralysis (AFP) specimens were analyzed across 16 laboratories. Ninety-two percent of specimens met the timeliness target for virus isolation, and 94% met the target for PCR-ITD. Genomic sequencing confirmed 20 cVDPV outbreaks in 10 countries. The establishment of new sequencing laboratories in Uganda and Nigeria reduced turnaround times, and a 2025 expansion plan aimed to build sequencing capacity in 12 additional countries. All laboratories assessed in 2024 for virus isolation, PCR-ITD, and environmental surveillance exceeded quality assurance accreditation thresholds and were rated “Pass”. The pilot implementation of Direct Detection Nanopore Sequencing (DDNS) techniques is expected to further strengthen genomic surveillance. Challenges remain, including stock out of essential supplies, uneven workloads, and infrastructure gaps. Conclusions: The African polio laboratory network has demonstrated sustained capacity, adaptability, and innovation in supporting polio eradication activities in the WHO African region. This study provides evidence on the importance of strengthening laboratory systems, expanding genomic capacity, and maintaining quality assurance mechanisms to support the final phase of polio eradication and broader public health surveillance.