While many developing countries were experiencing improved life expectancy and consequent socioeconomic progress over the last several decades, South Africa was moving in the opposite direction. Adult life expectancy (the mean age to which a 15-year-old can expect to live) decreased, and the number of deaths in South Africa nearly doubled from 1997 to 2006. These trends were driven by high death rates among both males and females in their 30s, a result at least in part of untreated HIV infection. A country that is losing its working-age population loses out on the productivity of a wide variety of public and private sector workers as well as the social capital generated by parenting and family life. For this country facing a number of significant challenges in socioeconomic development, untreated HIV had the potential to be the final nail in the coffin.
In 2004, South Africa began to provide antiretroviral therapy (ART) for HIV, and ART provision has increased steadily since then. A paper published last year by researchers working in KwaZulu-Natal measured the impact of ART on adult life expectancy in this South African province, an area of substantial poverty and HIV prevalence.1 Nurse-led programs in primary health clinics have enrolled 1 in 6 people in the province in HIV care and provided ART to 1 in 15. The outcome of these impressive achievements has been a rapid increase in adult life expectancy from 49.2 years in 2003 to 60.5 years in 2011. Mortality from all causes declined by over 50% in people aged 25 to 44 years old in the same period. The results are reflected nationally in a reversal of the upward trend in mortality and lower numbers of deaths in the working-age population since 2006. Furthermore, recent studies in a number of countries have demonstrated that ART use for HIV treatment is also slowing its transmission–a phenomenon called treatment as prevention–so the increase in ART use in South Africa is undoubtedly also decreasing the incidence of new infections in the country. Thus, while there are a number of factors influencing mortality data in South Africa, the single intervention of widespread ART use has contributed significantly to the reversal of some very dangerous trends.
A single intervention, yes, but one that was the product of decades of work spanning the full range of medical research:
- basic science research to identify the pathogen and the mechanism of the disease
- development of an accurate screening test
- epidemiology to recognize in whom, how, when, and where the disease occurred
- surveillance to observe any changes in the epidemiology
- discovery of compounds with antiretroviral activity
- animal studies and other nonclinical research to investigate the potential use of these compounds in humans
- clinical trials to assess the safety and efficacy of in humans
- behavioural studies to optimise outreach, access to and retention in care, patient adherence, and prevention of mother-to-child transmission
The success of ART in South Africa is just one example of how medical research matters—to individuals with a disease—to their caretakers and loved ones—to everyone at risk for developing a disease—and to the larger society to which all these people contribute.
1 Bor J, Herbst AJ, Newell M-J, Bärnighausen T. Increase in adult life expectancy in rural South Africa: valuing the scale-up of HIV treatment. Science. 2013;339:961-965.