Evaluation of the acute flaccid paralysis surveillance system in Windhoek District, Khomas Region, Namibia, 2020-2024

Introduction: Acute Flaccid Paralysis (AFP) surveillance is vital for early detection of poliovirus and is a cornerstone of the Global Polio Eradication Initiative (GPEI). Namibia was certified polio-free in 2008, but low AFP case detection in neighbouring countries places the country at risk of vaccine-derived polioviruses. We evaluated the AFP surveillance system in Windhoek District, Khomas Region, to assess its usefulness, examine key system attributes and determine whether the system is meeting its objectives. Methods: A descriptive cross-sectional study was conducted using United States Centre for Disease Control guidelines. Health programme officers, medical scientist, surveillance focal persons, nurses, and community health workers involved in AFP surveillance were recruited. Data from the national AFP line list (2020–2024) and completed case investigation forms were reviewed. Information on knowledge, usefulness, challenges, and system attributes were collected using pre-tested questionnaires and checklists. Univariate analysis was used to generate frequencies and proportions. Results: Of 20 health workers, 14 (70%) were female. Thirteen (65%) understood AFP case definitions and reporting forms, while 7 (35%) had poor knowledge. Ten (50%) had received AFP training. Only eleven AFP forms were completed of the 33 cases recorded in the National AFP line list. The district achieved 98% stool adequacy and a non-polio AFP rate ranged from 5.95/100,000 to 10.7/100,000 (mean: 7.85/100,000), which met World Health Organisation (WHO) targets. However, no health facilities records of meetings to discuss AFP data was available, no 60-day follow-up was conducted, and no contact tracing was done. Conclusion: WHO performance targets were met. The health workers lacked training. There was no evidence of surveillance data utilisation meeting records. The 60-day follow-up investigation and contact tracing was not conducted. Strengthening AFP surveillance capacity and inclusion of AFP surveillance data analysis and discussions in healthcare institutions’ meetings are essential to sustain Namibia’s polio-free status.