Implementation evaluation of the COVID-19 vaccination: Speed, equity and mortality trends

Background: The coronavirus disease (COVID-19) vaccination campaign in South Africa constituted the most significant public health intervention in recent history, occurring against the backdrop of a prevailing quadruple burden of disease. Aim: To evaluate the implementation of the COVID-19 vaccination campaign, focusing on rollout speed and geographic equity and to examine the temporal associations between vaccination coverage and mortality trends. Setting: All South African residents aged 12 years and older who were eligible for COVID-19 vaccination during the study period. Methods: A retrospective, ecological population-based time-series analysis to assess vaccination rollout trends and geographic equity, and to examine the association between vaccination coverage and excess mortality. The Logic Model and the RE-AIM (Reach, Effectiveness, Adoption, Implementation and Maintenance) framework were applied to interpret implementation performance. Results: The vaccination campaign expanded rapidly in the early phases, but vaccination activity declined significantly over a three-year period (p < 0.001). By February 2024, approximately 49.7% of the eligible population had received at least one dose, below the national target of 67%. Coverage was higher in metropolitan than in district municipalities (p < 0.05). Statistically significant non-causal temporal associations were observed between vaccination coverage and excess mortality. Conclusion: Early vaccine coverage was achieved, but uptake was insufficient to meet national coverage targets. Geographic disparities suggest potential inequities in access, offering empirical insights to strengthen primary health care integration, equitable service delivery, and data-driven implementation strategies. Contribution: This study supports dual-framework implementation science for evaluating large-scale public health interventions to inform health system strengthening and emergency preparedness.