Drop in infections follows ARVs' success
21 Feb 2013 20:00 | Mia Malan
The adult life expectancy in the general population in rural KwaZulu-Natal has increased by more than eleven years – from 49 to 60 - as a result of the widespread availability of anti-retroviral treatment (ART). That's according to a study conducted by the Africa Centre for Health and Population Studies at the University of KwaZulu-Natal, which was published on Friday in the leading international scientific journal Science.
The study measured trends in adult life expectancy between 2000 and 2011 among 101 000 people in Umkhanyakude district in the province.
In the early 2000s adult life expectancy in the community drastically declined to 49.2 years. But, with ART becoming available at public health facilities the average life expectancy in the community began to increase, and reached 60.5 years by 2011. "Before ART became widely available, most people were dying in their 30s and 40s. Now people are living to pension age and beyond," said lead study author, Jacob Bor.
According to the director of the Africa Centre, Marie-Louise Newell, community members have clearly seen the impact of the reduction in death rates. "Whereas six years ago there was at least one funeral every weekend, it's now more like one a month," she said. "The health department's rapid scale-up of ART in this region has achieved massive results."
Senior study author Till Bärnighausen said this study is the first that measured the average life expectancy of everyone in the community and compared it to the life expectancy of community members who are not dying of HIV-related causes. "We found that in 2011 the life expectancy of those not dying of HIV-related causes, that is, a measure of what total life expectancy in this community could be without the impact of HIV, was still 10 years higher at 70 years than total life expectancy among the general population at 60 years. This difference of about ten years is likely due to the fact that only six out of ten HIV-infected people who need ART currently receive it. As more people gain access to ART the general life expectancy will most likely further increase," he said.
The study also measured the cost-effectiveness of the treatment programme comparing it to the number of life years gained at the population level between 2004 and 2011 to the costs of providing ART over this period. The ART programme saved an additional year of life for $1 593 – less than a quarter of the average South African's annual income of $6 960 in 2011. The cost of saving a life year included the charges of running a rural ART programme such as the medicine itself and health workers' salaries.
ART halts spread of HIV
Another study by the centre that will also be published in Science on Friday has demonstrated that HIV incidence – the rate at which new HIV infections occur – is considerably lower in areas where ART is widely available. An HIV-negative person was nearly 40% less likely to become infected with HIV in areas where between 30% and 40% of HIV-infected people were on ART, than in areas where only 10% of HIV-positive people were on ART.
This is because ART greatly reduces the amount of HIV in an infected person's body, which makes the individual far less likely to pass on the virus.
While several previous studies have shown that ART substantially lowers the probability of HIV transmission, there has been vigorous debate "whether significant population-level reductions in the rate of new HIV infections could be achieved in ‘real-world' sub-Saharan African settings" where "stable cohabitating couples" are often not the norm and where "significant operational challenges exist" to the successful delivery of treatment to huge numbers of patients.
This study is the first that has shown that a slowdown in the rate of new HIV infection as a result of access to ART is indeed possible in an African community.
Researchers used data from one of Africa's largest population-based studies to follow 16 667 HIV-negative individuals in rural Kwazulu-Natal between 2004 and 2011.
It is the first time the positive impact of ART on the rate of new HIV infections has been demonstrated in a community setting. "While key questions remain about durability of protection, long-term adherence and transmission of ART-resistant strains to partners, our results suggest that commitment to further increasing ART coverage in sub-Saharan Africa can contribute significantly to meeting the Political Declaration of the United Nations General Assembly of halving sexual transmission of HIV by 2015," the study authors said.
View the original online publication here