DURBAN, South Africa– The conference was opened with a keynote address by South African President Thabo Mbeki – a talk that dispirited many of the 12,700 delegates in Durban because Mbeki refused to denounce the dissident opinion that HIV does not cause AIDS.
Instead Mbeki asked for a six-month study by eminent scientists on outstanding questions about the causes of AIDS, questions most of the scientists thought had been determined years ago.
While Mbeki never said he did not believe that AIDS is caused by HIV, he emphasized poverty as the major cause of AIDS in South Africa where 4.3 million people are estimated to be infected with the disease. As many as 30 percent of the women giving birth in Durban are HIV-infected.
Researchers reported a bleak outlook for the future of Africa and the developing world: –One report predicted that the epidemic was so prevalent in South Africa, Zimbabwe and Botswana that those countries would actually begin to experience a decrease in population – the first time since the Black Death of the Middle Ages that illness reduced a nation's population.
–Another report estimated that within 10 years, in developing countries, more than 44 million children – 40 million of them in Africa –will be classified as orphans, having lost one or both parents. In some of the countries, particularly in southern Africa, one out of three children under the age of 15 will have lost a parent by the year 2010. About 70 percent of those children will have lost a parent to AIDS. –Of the children who are 15, half of them will die of AIDS in some countries before they are 30.
In contrast to the remarks of President Mbeki, Nelson Mandela, the former South African president who ended apartheid there, closed the conference with an urgent call to arms to fight HIV/AIDS on the continent and in the world – a speech that electrified the delegates and soothed the spirits of those who were upset with Mbeki.
`Let us not equivocate,’ Mandela said, ‘a tragedy of unprecedented proportions is unfolding in Africa. AIDS in Africa is claiming more lives than the sum total of all wars, famines and floods, and the ravages of such deadly diseases as malaria.'
Mandela said scientists and people need to use current knowledge to fight the disease with improved education, preventive tactics and safe sexual practices. He decried that ‘so much unnecessary attention around this conference had been directed toward a dispute that is unintentionally distracting for the real life and death issues we are confronted as a country, a region, a continent and a world.'
`The challenge is to move from rhetoric to action,’ Mandela said to the enthusiastic applause from the delegates, ‘and action at an unprecedented intensity and scale. AIDS is clearly a disaster, effectively wiping out the development gains of the past decades and sabotaging the future.'
Providing antiretroviral drugs to reduce the risk of mother-to-child-transmission of human immunodeficiency virus is just part of the equation in preventing newborns from contracting the deadly infection – especially in developing countries.
Numerous studies presented at the XIII International AIDS Conference were able to demonstrate that short-course treatments with nevirapine or zidovudine (AZT) cut the risk of transmission at birth by 40 percent or more.
But other studies also revealed that the gains made in preventing transmission at birth are eroded because the virus can be transmitted during breast feeding, especially if breast feeding occurs for more than six months or if the baby is not exclusively breast fed during the first half-year of life.
`‘We are seeing that preventing HIV-infection in babies is a complex problem,’’ said Helene Gayle, director of the National Center for HIV, STD and TB Prevention at the Centers for Disease Control and Prevention (CDC) in Atlanta.
`‘The drugs work,’’ said Stefan Wiktor, associate director for science at the CDC, "but there is a problem in keeping the children free of infection because often there is no acceptable alternative to breast milk for nutrition."
In one study in Uganda, a single dose of nevirapine to the mother in labor and one dose to the child after delivery appeared to prevent transmission for at least as long as 18 months – even if women were breast feeding.
In a South Africa study, researchers found that nevirapine was equivalent to AZT in protecting children from being infected by the mother. Early results of that trial found a transmission rate of 12.7 percent in mother-child pairs treated with nevirapine and a 9.5 percent infection rate in the mother-child pairs getting AZT, said Daya Moodley, MD, a researcher at the University of Natal, Durban.
In the West African nations of Cote d'Ivoire and Burkino Faso, US researchers working with the National French AIDS Research Agency, treated the HIV-infected mothers of 641 children with AZT or placebo. After six weeks, Wiktor said, 14 percent of the children on AZT were infected with HIV, the virus that causes AIDS, while 23.6 percent of the children who received the placebo pills were infected.
Structured treatment interruptions
In other developments at the conference, very preliminary results suggest that structured treatment interruptions in complex anti-AIDS therapy might allow substantial reductions in the amount of medication a patient requires.
`‘We are not at all suggesting that conclusive evidence shows this is a useful therapy,’’ said Dr. Mike Dybul, a researcher in the Laboratory of Immunoregulation at the National Institute of Allergy and Infectious Disease (NIAID), Bethesda, Md., said. ‘‘It is intriguing information,’’ Dybul said.
Dybul discussed two studies being conducted under the leadership of Dr. Anthony Fauci, director of the NIAID. He presented data on nine patients on a regimen that allowed them to be on drugs for two months and then off drugs for a month; and on five patients on a week-on, week-off protocol. So far, Dybul said, no signs of drug resistance have appeared, virus rebound has been generally controlled, and CD4 cell numbers remain stable. Some patients have been on the program more than a year. However, much more information needs to be obtained before STI of any time interval is recommended.
3 can be better than 4
If three drugs works well to combat HIV, shouldn't four such drugs work even better.
Apparently not, reported Dr. Joseph Eron, associate professor of medicine at the University of North Carolina-Chapel Hill.
`‘I think we need more potent regimens to deal with human immunodeficiency virus,’’ Eron said ‘‘but those regimens need to be more compact.’'
He discussed results from a 64-week study, demonstrating that when regimen dropouts were figured in the results, patients on the three-drug combination did better than those getting four drugs.
The three-drug patients received a standard regimen of nelfinavir, zidovudine and lamivudine (3TC). The other cohort received amprenavir, abacavir, zidovudine and lamivudine.
Spermicide fails in HIV test
A spermicidal used for 50 years, often in combination with condoms and diaphragms, not only fails to protect against sexually transmitted diseases but may enhance infection with the AIDS virus.
"It is an understatement to say that we were extremely disappointed to find out that there were more seroconversion (infections with HIV, the virus that causes AIDS) among the women in the nonoxynol-9 arm of the study than among placebo users," said Dr. Lut van Damme, lead investigator from the Institute of Tropical Medicine, Antwerp Belgium.
In the study of 999 commercial sex workers in South Africa, Benin, Cote d'Ivoire and Thailand, researchers compared nonoxynol-9 to a vaginal lubricant. Van Damme said there were 59 HIV infections among the women using nonoxynol-9, while the placebo group had 41 infections. Nonoxynol-9 was no better than the lubricant in protecting against gonorrhea or chlamydia infections.
However, researchers said there may be more microbicides in the pharmaceutical development pipeline. Dr. Mark Wainberg, director of the McGill AIDS Centre, Montreal, said that reformulation of antiretrovirals might be useful in preventing transmission of disease during sex.
Webcast– Durban conference global outreach
This site will prolong the accessibility of the information from the conference well after delegates have returned home. The conference organisers expect hundreds of thousands of visits to the site during its 18-month life. The site will remain freely accessible until December 31, 2001 by financial sponsorship from the biopharmaceutical company Gilead Sciences Inc.
HIV/AIDS Websites of interest:
ProCAARE: The Program for Collaboration Against AIDS and Related Epidemicshttp://www.healthnet.org/programs/procaare.html
Swiss information and exchange site created by Fondation du Présenthttp://www.hivnet.ch
Panafrican News Agencyhttp://www.africanews.org/PANA
National Institute of Allergy and Infectious Diseases (NIAID) –vaccine developmenthttp://www.niaid.nih.gov/daids/vaccine/