HIV drugs 'can defend against new infections'
[MEXICO CITY] Antiretroviral drugs can be used to prevent new HIV infections, according to research presented at the International AIDS Conference in Mexico City this week (5 August).
The research, from the British Columbia Centre for Excellence in HIV/AIDS (BC-CfE) in Canada, found a strong link between the use of highly active antiretroviral therapy (HAART) and prevention of new infections.
"We've known for some time that the expansion of coverage with HAART could help to reduce the number of new HIV infections," said Julio Montaner, director of BC-CfE and president-elect of the International AIDS Society. "However, we were amazed at the actual number of new infections that can be potentially averted by expanding access to treatment."
According to the study, published in a July issue of the Journal of Infectious Diseases, increasing HAART coverage from the current level of 50 per cent to 75 per cent would cut new infections by a third.
This was calculated from a model based on HIV treatment in Canada.
"The fact that treatment is the central part of prevention should re-energise our willingness to bring the treatment to the people now," said Montaner.
Observational studies in Uganda have also shown that in heterosexual couples where only one is HIV positive, the likelihood of the negative person being infected is low when the positive person has a low amount of virus in their blood. The intention of ART is to decrease this viral load.
"We are in a desperate race against time to find a protection that works," said Stephen Lewis, the former UN secretary-general's special envoy for HIV/AIDS in Africa. "If this takes hold it will have a bigger impact than any of the other protection methods."
Elly Katabira, associate professor of medicine at Makerere University, Uganda, stressed the effect that treatment may have on protection in Africa.
"Many of our patients we initiate on ART are very sick and some have been close to death," he said. "When they get better, they become better ambassadors of prevention. They talk about prevention because they don't want other people to be where they were before and that is one of the ways treatment could promote prevention."
But rolling out ART must come as part of a comprehensive package, stressed Lewis. "There's no point having effective ART in African communities if for instance nutrition and food security concerns are not addressed at the same time."