Tegegn, Tesfalem AbateTerefe, Yibeltal A.2025-09-042025-09-042025-10Tegegn, T.A. & Terefe, Y.A. 2025, 'Contribution of the 2021 COVID-19 vaccination regime to COVID-19 transmission and control in South Africa : a mathematical modeling perspective', Chaos, Solitons and Fractals, vol. 199, art. 116870, pp. 1-14, doi : 10.1016/j.chaos.2025.116870.0960-0779 (print)1873-2887 (online)10.1016/j.chaos.2025.116870http://hdl.handle.net/2263/104216DATA AVAILABILITY : We used open-access COVID-19 data from the Johns Hopkins University Coronavirus Resource Center ( https://github.com/CSSEGISandData/COVID-19, with full citation provided in the manuscript).Please read abstract in the article.en© 2025 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).COVID-19 pandemicVaccinesBasic reproduction numberStabilitySensitivity analysisSevere acute respiratory syndrome coronavirus 2 (SARS-CoV-2)Article