World AIDS Day - There is no magic bullet to solve the AIDS problem
Today is Worlds AIDS Day. Nearly three decades on since the first such day in 1988 what’s the situation report on the fight to combat the disease? A leading South African epidemiologist and global figure in HIV/AIDS research tells it straight. STEPHEN COAN reports.
“There is no magic bullet to solve the AIDS problem,” according to Professor Salim S. Abdool Karim, referring to the Joint United Nations Programme on HIV/AIDS (UNAIDS) 90-90-90 initiative launched in 2014 which aims to end the AIDS epidemic by 2030 with 2020 as the target year when 90% of those living with HIV will know their status, 90% with HIV will be on antiretroviral therapy and 90% of those will have viral suppression.
“Globally, we have set an ambitious target to end Aids as a ‘public health threat’,” said Abdool Karim. “People tend to overlook the last bit. They only see 90-90-90 as ending AIDS. We cannot end AIDS anytime soon since there are 37 million people living with AIDS worldwide and there’s no cure. So AIDS is not going to go away anytime soon.”
“We need to reduce the number of infections in order to reach a point where the epidemic is under control. This is what is meant by ending AIDS as a public health threat”
Africa has 70 per cent of all HIV infections while southern and eastern Africa accounts for half of all global infections. In 2015, an estimated seven million South Africans were living with HIV while the same year saw 380 000 new infections and the deaths of 180 000 people from AIDS-related illnesses.
There is no doubt 90-90-90 is a big ask for South Africa. “Our country has a generalised epidemic with large numbers of the population affected. We have to aim for high proportion of people living with HIV being virally suppressed in order to reduce the spread of the virus to others. In order for that to happen people have to know they have HIV and to take treatment diligently.”
Something that didn’t happen here initially thanks to government-endorsed AIDS denialism but now government policy has been reversed and anti-retroviral (ARV) treatment is readily available have we rewound the clock? “You can never make up for lost time once it’s gone,” said Abdool Karim. “The Mbeki era denied several million people ARV treatment, many of those individuals died. But what we did do during that time enabled the country to catch up quickly once things changed in 2009, when ARV roll-out went to scale post-Mbeki.”
During the denialist period, funding was not accessible to provide AIDS treatment from the South African government or the Global Fund due to that body’s undertaking to work only through the government. But such constraints did not apply to the U.S. President's Emergency Plan for AIDS Relief (PEPFAR). “So research centres such as CAPRISA and many other NGOs were already diagnosing and treating AIDS during the Mbeki era with PEPFAR funding. Accordingly, when government reversed its stance we had a rolling start, not a standing start, and we could scale up treatment much faster.”
Stigma and denialism within communities was also decreasing. “Ending discrimination at ground level is critical and treatment made that possible,” said Abdool Karim. “In one of our study areas sick people were being brought to our clinic in wheelbarrows. After two weeks of antiretroviral treatment they would come back healthy and say ‘I’m going back to work’. Treatment made the denialists look silly.”
The post-2009 government intervention has been nothing short of miraculous, according to Abdool Karim. “Life expectancy has increased, people are living about 10 percent longer. Post HIV, life span was about 50 years, now its 55 to 60 years. That is due to the decrease in AIDS related deaths thanks to treatment.”
“The other big positive is that South Africa turned HIV transmission from mother to child around, it was 25 to 30 percent about 10 years ago while today, it’s one to two percent. Fifteen years ago most children born with HIV died before the end of their second year. Now they don’t. So we have a generation of HIV free children.”
All the more tragic that those saved from infection as infants should now be getting HIV as teenagers. “In young girls, from teenagers to young women in their early twenties, we are seeing high rates of infection and high vulnerability to infection. One of the main reasons for this risk in young women is sex with men in their thirties who are HIV-positive.”
The vulnerability in young women is probably both behavioural and biological. At the recent AIDS conference, a bacteria, Prevotella bivia, currently the subject of a CAPRISA study, found in large amounts in the vaginas of younger women, increases the chances of HIV infection in women.
The age disparity in sexual activity was first identified in a 1990 study done by his wife, Professor Quarraisha Abdool Karim, Associate Scientific Director of CAPRISA and a member of the UNAIDS Scientific Expert Panel and Scientific Advisor to the Executive Director of UNAIDS. Follow up studies show that it is now entrenched with even higher infection rates.
“When you ask teenage girls why they are having sex with older men and not with those within their own age group they say ‘what’s an 18 year-old boy got for me? What do I get? What presents do I and the family get?’ It’s a quid pro quo activity.”
“In the communities where we conduct our research, people do not take the view that the age disparity among partners is wrong. It is part of the problem: we are fighting something that has become accepted. It’s really a challenge.”
The Abdool Karims have now spent nearly three decades working towards slowing the rate of new infections in teenage girls. “It became our life’s calling to find solutions to that problem.”
The solution proved elusive until the appearance of an antiretroviral drug called Tenofovir. A CAPRISA study tested a microbicide gel containing Tenofovir and found that it was effective in preventing HIV transmission in women, cutting the infection rate by 39 percent overall and 54% in women who used the gel diligently.
That was the good news but compliance to the necessary medication regime proved a stumbling block in subsequent studies of both gels and pills. “If you are a healthy woman why should you protect yourself against an infection you might not get? It was a tall order. Some women don’t see themselves at risk while others are not able to take control of their lives and do it for themselves.”
Now the Abdool Karim’s are hoping for better success using broadly neutralising antibodies, so-called because they are able to kill multiple strains of HIV. Rare individuals make such antibodies. One such person is known only by the codename CAPRISA 256. “For over a decade she has developed very unusual antibodies.”
“The HI-virus hides its proteins under a layer of sugar, rather like a smartie sweet,” said Abdool Karim. “We found that this woman’s antibodies have ‘long arms’ that can reach through the sugar shield to reach the viral protein and neutralise the virus. CAPRISA 256 has one of the most potent antibodies in the world.”
However, their colleagues, Lynn Morris and Penny Moore from the National Institute of Communicable Diseases in Johannesburg found that this antibody works better for the Subtype C virus found in southern Africa than for the Subtype B virus found in U.S. and Europe. Hence, the CAPRISA researchers have teamed up with the National Institutes of Health in the U.S. to combine the CAPRISA antibody with others that are more effective Subtype B viruses.
“We hope to have both antibodies to put into humans by the middle of 2017,” said Abdool Karim. “The monkey studies with the CAPRISA 256 antibody are very promising but that doesn’t mean it will work in humans. It will be a five-year development programme just to see if it does work and that it is safe. Only then will we consider production. In scientific medicine, developing new treatments is not achieved quickly.”
The same applies for a cure to the disease. “This virus is ‘smarter’ than us at the moment; it presents a challenge by hiding deep in our cells that is currently beyond our ability to defeat it. But we will outsmart it, but we need the time; we are unlikely to have a cure anytime soon.”
Abdool Karim is optimistic that a vaccine will eventually be produced. “Research in this country is world-class, we are right up there in the front line with the support of funders from the United States and local funders like the National Research Foundation, Medical Research Council and the Department of Science and Technology. While the existing laboratory technology is enabling scientists to understand the virus better, the new technologies coming along will open up further ways of understanding the virus. I am confident that the scientific progress we are making in AIDS will place us in a good position to defeat this virus and save millions of lives.”
This article was written by Stephen Coan and is published in The Star today (1 December 2016)
Prof Abdool Karim