Addressing the plenary session at the 4th South African AIDS Conference, Professor Bruce Walker of the Ragon Institute at Harvard University told the more than 4 000 delegates that some of these HIV or elite controllers have been infected for over 30 years, but never suffered any adverse condition or opportunistic infection despite an absence of anti-retroviral treatment.

Scientists are now studying over 300 people in South Africa and the United States in the hope of learning more about HIV which he described as ‘€œone of the most daunting problems science has ever had to address’€.

He said these elite controllers were also less likely to transmit the virus as their viral load was often undetectable. ‘€œWe need to find the signals indicating what are involved in controlling HIV and we are discovering that these elite controllers are able to make the virus less fit once it gets into their bodies. The virus is forced into a configuration where it does not replicate as effectively,’€ Walker explained.

Scientists were able to take CD4 cells (critical to control infection and a measure of immunity), infect it with HIV and add CD8 T cells into the mix. Researchers saw a dramatic drop in the amount of HI-Virus produced, which according to Walker illustrated that the body’€™s CD8 T Cells were making the virus less ‘€œfit’€.

‘€œThese CD8 T Cells drive the virus into something that is less likely to cause disease,’€ said Walker.

Presenting at the same session Professor Robin Wood, Director of the Desmond Tutu HIV Centre at the University of Cape Town warned that South Africa was facing a medical catastrophe with the rapid increase in HIV and TB co-infection.

‘€œWe are accelerating away from the Millennium Development Goals with the fifth highest TB burden in the world, but the highest if you measure the per capita burden,’€ Wood revealed.

Research conducted among a community in Cape Town which recorded a 23% HIV prevalence found that over the last 10 years there had been a dramatic increase in TB. Further research revealed high TB infection rates among school children and Woods was able to show that mean annual risk of contracting TB among the school children was 4%, extremely high compared to international trends of less than 1%.

‘€œThe risk was increasing as the children get older, but it should be decreasing,’€ Woods said.

Researchers then turned to the adolescents in the community and found that the annual risk of TB infection for 16 year olds was over 10%, also very high. Woods said this data presented evidence for the establishment of TB case finding by tracing the contacts via the children. This in turn would lead to increased case finding, the Achilles heel of South Africa’€™s TB programme, where case detection is sub-optimal.

Woods also presented evidence that anti-retrovirals were having a significant effect on reducing TB infection in the community they studied, but that it could be more dramatic if younger people were recruited into the ARV programme.

‘€œAt the moment we are closing the door after the horse has bolted (targeting older people). We need to reach the HIV positive young people before they get TB and get them onto treatment,’€ he said.

Dr Francois Venter, President of the HIV Clinicians Society called for the introduction of drugs that could replace d4T, a highly intolerable anti-retroviral responsible for most of the drug toxicity cases in South Africa, but one of the first line drugs dispensed at government facilities.

The replacement drug tenofovir is ten times the price of d4T.

He also pointed out that South Africa ‘€œis not doing well’€ in terms of the targets to get people onto anti-retrovirals. The National Strategic Plan target is 80% of all those needing treatment, while 2007 figures were at 30%. ‘€œThe rest of the people are going to end up with ghastly infections and we have astonishing death rates while we wait to get people on drugs,’€ Venter said.