SACEMA scores first in-house PhD

Carel Pretorius recently became the first student working at SACEMA (DST/NRF Centre of Excellence in Epidemiological Modelling and Analysis) at Stellenbosch University (SU) to complete a PhD degree after successfully defending his PhD thesis.

His thesis was titled: “An investigation into joint HIV and TB epidemics in South Africa”. The work was supervised by Prof Kristian Müller-Nedebock of the Physics Department at SU. The event was the culmination of a long and unusual academic journey, which enabled him to take a multidisciplinary approach in his investigation of HIV and TB epidemics in South Africa. Mr Pretorius completed his first degree, in land surveying, at the University of Pretoria in 1997. He then moved to the University of the Witwatersrand and did an honours degree in pure mathematics in 1999 and an MSc in applied mathematics in 2006.

He joined SACEMA to study HIV and TB epidemics in South Africa. Using a unique data set from a thoroughly studied HIV-TB epidemic in Masiphumelele (a township near Cape Town), he developed a mathematical model which not only confirmed many expectations but also led to an unexpected result: ART treatment has the potential to control HIV transmission at a community level, indirectly also controlling the TB epidemic.Carel_John

He extended this analysis to HIV-TB epidemics at a national level, and developed models to account for demographical detail, adapting tools from fields as far apart as applied demography and statistical physics. His research results can best be described as a framework for integrating available epidemiological data, locally and nationally, with a toolkit of mathematical methods which can be continuously sharpened in accordance with the ever-changing (but not necessarily improving) picture of HIV and TB epidemics in South Africa.

His work shed new light on the interplay between demographical and epidemiological processes, for example, on the role of intergenerational sex on the spread of HIV and provides methods for quantifying uncertainty in epidemiological models. The World Health Organization (WHO) have organized a special meeting to be held on 2-6 November 2009 titled: “Treatment for prevention” where a possible new intervention of using antiretroviral treatment to both treat HIV patients and to limit the spread of HIV will be debated. Mr Pretorius has been invited to attend this meeting and it is his hope that his modelling work could influence policy making at this high level.

Caption: Carel Pretorius pictured here with Prof John Hargrove, Director: SACEMA.