Researchers from the Africa Centre for Health and Population Studies presented the results, which show that in areas where antiretroviral therapy uptake is high, people who do not have HIV are 38 per cent less likely to acquire the virus than in areas of low uptake.
"These findings are extremely important. UNAIDS encourages all countries and communities to achieve high coverage of antiretroviral therapy, both for the benefit of people living with HIV and for the communities in which they live," said Paul De Lay, Deputy Executive Director of the Joint UN Programme on HIV/AIDS (UNAIDS).
The findings also confirm results from a recent study which state that if an HIV-positive person adheres to an effective antiretroviral therapy regimen, the risk of transmitting the virus to their uninfected sexual partner can be reduced by 96 per cent.
This is the first time that the impact of antiretroviral therapy on HIV incidence has been demonstrated in a community setting. The study used data collected since 2003 in a rural area of KwaZulu-Natal in South Africa. In this area, 20,000 people living with HIV had accessed antiretroviral therapy since 2004 through public primary health care.
From 2004 to 2011, 16,500 HIV-negative people were followed through population-based HIV surveillance. During the study period 1,413 people were newly infected with HIV " an incidence rate of 2.6 per cent.
In areas where more than 30 per cent of all people living with HIV were receiving antiretroviral therapy, the incidence rate was significantly lower, as people were nearly 40 per cent less likely to acquire HIV than in low uptake areas.
In recent years, South Africa has expanded the eligibility criteria for initiation of antiretroviral therapy in line with the 2010 recommendations by the UN World Health Organization (WHO).