An article published in the Journal of Theoretical Biology considered an HIV/AIDS model in the presence of an HIV testing and screening campaign (1). Reduction of new HIV infections by implementing a comprehensive national HIV prevention programme at a sufficient scale to have real impact remains a priority. The formulated model is analyzed and fitted to the South African prevalence data from UNAIDS (2). It was concluded that the future of the epidemic largely depends on changes in behaviour. The current HIV counselling and testing program's intent of testing 15 million individuals in two years is noble but questions still remain on whether the response of individuals in the population will match the intended purpose. The rate of screening must be above a certain threshold for the campaign to have a significant impact in reducing the prevalence and generation of new infections. The model predicts that the current levels of screening are approximately 1.6 million individuals per annum. Increasing this value to 7.5 million per annum will be a milestone. Projections show a slight decline in the next five years under the present levels of interventions. The model presented in the paper is consistent with previous models on the HIV/AIDS epidemic in South Africa (3,4,5) and the reports from the WHO (2). Although the models differ in their exact formulations, they are consensual in the conclusion that the situation remains gloomy unless there is a drastic change in the approach to the epidemic. The models predict the stabilisation of the prevalence at values above 15% in the next decade. The model provides useful insights into the possible impact of the HIV testing and screening campaign on the dynamics of HIV/AIDS in South Africa.
- Nyabadza F, Mukandavire Z. Modelling HIV/AIDS in the presence of an HIV testing and screening campaign. J Theor Biol. 2011;280: 167-179. Link to article
- UNAIDS/WHO. Epidemiological fact sheets on HIV and AIDS, 2008 update. http://www.who.int/hiv/pub/epidemiology/pubfacts/en/ Accessed 29 August 2011.
- Johnson LF, Dorrington RE. Modelling the demographic impact of HIV/AIDS in South Africa and the likely impact of interventions. Demographic Research. 2006;14: 541-574. Link to article
- Nicolay N. HIV and AIDS scenarios for South Africa: 2005-2025 http://www.livethefuture.co.za/docs/LIFE%20THE%20FUTURE%20-%20Overview.pdf Accessed 29 August 2011.
- Rehle TM, ShisanaO. Epidemiological and demographic HIV/AIDS projections: South Africa. Afri J AIDS Res. 2003;2: 1-8.