Advancing Epidemiological Modelling for Public Health Impact through the DSI-NRF Centre of Excellence in Epidemiological Modelling and Analysis (SACEMA)

For nearly two decades, SACEMA has played a leading role in understanding and managing infectious diseases. SACEMA applies mathematical modelling to improve public health responses to diseases such as human immunodeficiency virus (HIV), tuberculosis (TB), human papillomavirus (HPV), measles, polio trypanosomiasis, and other infectious diseases.

SACEMA played a vital role during the COVID-19 pandemic by providing early forecasts and tracking the epidemic’s change over time and how the virus spread across Africa. SACEMA’s researchers were involved in the South African COVID-19 Modelling Consortium (SACMC), helping to develop models to project incidence, mortality, and healthcare needs. As part of SACMC, and in partnership with other institutions, SACEMA helped to develop models and dashboards, which guided the South African Government’s  strategic planning. In addition, SACEMA’s early characterisation of the Omicron variant increased understanding of transmission dynamics and the increased reinfection risk. SACEMA’s input influenced national control measures and vaccination strategies and helped to inform high-level engagements with the World Health Organization (WHO), and the United States of America (USA) and United Kingdom (UK) governments. This enhanced global situational awareness, which helped to reduce transmission and save lives. In this way, South African communities, healthcare providers, policymakers, and international governments all benefitted from SACEMA’s research.

In HIV research and control, SACEMA developed a method for estimating HIV incidence, which was adopted by the US Centers for Disease Control and Prevention (CDC). SACEMA also leads the Secretariat of the Joint United Nations Programme on HIV/AIDS (UNAIDS) Reference Group on Estimates, Modelling, and Projections. The Reference Group  provides guidance on the mathematical methods used to generate HIV estimates, strengthening responses to HIV epidemics worldwide. In addition, SACEMA’s modelling of male circumcision and treatment as prevention informed international public health policies. This research has benefitted communities with a HIV/AIDS burden, public health officials, and other researchers in the field.

 By modelling the impact of HPV vaccination and screening on cervical cancer, SACEMA provided critical evidence supporting new prevention strategies. This helped to shape the WHO’s Cervical Cancer Elimination Modelling Consortium and contributed to South Africa’s Cervical Cancer Elimination Strategy to reduce cervical cancer deaths.

SACEMA’s collaboration with the Desmond Tutu TB Centre contributed to groundbreaking studies in TB prevention. The partnership supported routine TB surveillance, and developed epidemiological models to directly inform effective control strategies.  As part of the TB Think Tank, SACEMA provided essential data and models to advise the National Department of Health on evidence-based TB prevention and control policy and programmes. This led to  reducing TB cases, better management and reducing TB deaths, benefiting communities affected by TB, researchers and South African public health officials.

SACEMA also worked with the National Institute for Communicable Diseases (NICD), to strengthen disease surveillance in South Africa. During the 2017-2018 listeriosis outbreak, SACEMA developed models to assess the impact of a nation-wide recall of processed meat. Providing weekly reports during the 2023 measles outbreak supported decision-making. Additionally, SACEMA developed models as poliovirus was circulating in Southern Africa. The  longstanding strategic relationship between SACEMA and the NICD reflects a commitment to integrating research with practical health outcomes. It has empowered stakeholders to implement timely and effective interventions, mitigating the impact of major communicable diseases in South Africa. 

SACEMA also actively promotes public engagement by hosting workshops, seminars, and public talks, and writing lay articles to improve community understanding and support for public health initiatives.Furthermore, as a major player in modelling capacity building on the continent, SACEMA hashosted international clinics on infectious disease dynamics and data. Nearly 200 postgraduate students have obtained degrees in epidemiological modelling or analysis with SACEMA’s support. SACEMA’s innovative Policy Modelling Fellowship  focuses on building sustainable expertise in infectious disease modelling within the departments of health across the continent. Fellows from Eswatini, Malawi, South Africa, and Zimbabwe have been upskilled to interpret data and apply it to models.These capacity building efforts have fostered a new generation of researchers with advanced epidemiological modelling skills, for improved public health decision-making across Southern Africa.