Systems dynamics approach for modelling South Africa’s response to COVID-19: A “what if” scenario

  • Shingirirai Savious Mutanga
    Council for Scientific and Industrial Research (CSIR), Smart Place Cluster, Holistic Climate Change-Climate Services Group, Pretoria, South Africa.
    https://orcid.org/0000-0003-0065-0129
  • Mercy Ngungu
    Human Sciences Research Council Developmental, Capable and Ethical States, Pretoria, South Africa.
  • Fhulufhelo Phillis Tshililo
    Department of Quality and Operations Management, Faculty of Engineering and Built Environment, University of Johannesburg, South Africa.
    https://orcid.org/0000-0001-7338-2183
  • Martin Kaggwa
    Sam Tambani Research Institute, Johannesburg, South Africa.

ABSTRACT

Background: Many countries in the world are still struggling to control COVID-19 pandemic. As of April 28, 2020, South Africa reported the highest number of COVID-19 cases in Sub-Sahara Africa. The country took aggressive steps to control the spread of the virus including setting a national command team for COVID-19 and putting the country on a complete lockdown for more than 100 days. Evidence across most countries has shown that, it is vital to monitor the progression of pandemics and assess the effects of various public health measures, such as lockdowns. Countries need to have scientific tools to assist in monitoring and assessing the effectiveness of mitigation interventions. The objective of this study was thus to assess the extent to which a systems dynamics model can forecast COVID-19 infections in South Africa and be a useful tool in evaluating government interventions to manage the epidemic through ‘what if’ simulations.
Design and Methods: This study presents a systems dynamics model (SD) of the COVID-19 infection in South Africa, as one of such tools. The development of the SD model in this study is grounded in design science research which fundamentally builds on prior research of modelling complex systems.
Results: The SD model satisfactorily replicates the general trend of COVID-19 infections and recovery for South Africa within the first 100 days of the pandemic. The model further confirms that the decision to lockdown the country was a right one, otherwise the country’s health capacity would have been overwhelmed. Going forward, the model predicts that the level of infection in the country will peak towards the last quarter of 2020, and thereafter start to decline.
Conclusions: Ultimately, the model structure and simulations suggest that a systems dynamics model can be a useful tool in monitoring, predicting and testing interventions to manage COVID-19 with an acceptable margin of error. Moreover, the model can be developed further to include more variables as more facts on the COVID-19 emerge.

AUTHOR BIOGRAPHIES

Shingirirai Savious Mutanga, Council for Scientific and Industrial Research (CSIR), Smart Place Cluster, Holistic Climate Change-Climate Services Group, Pretoria

Department of Quality and Operations Management, Faculty of Engineering and Built Environment, University of Johannesburg

Fhulufhelo Phillis Tshililo, Department of Quality and Operations Management, Faculty of Engineering and Built Environment, University of Johannesburg

Developmental, Capable and Ethical States, Human Sciences Research Council, Pretoria

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