SciDev.Net

This special issue is a large collection of opinion pieces, research and review articles, and news features that highlight the advances in knowledge and challenges to the treatment and prevention of HIV/AIDS, including articles on randomised trials of promising HIV drugs.

It also includes a look at the preventive potential of microbicides and prophylactic HIV drugs. Another key issue covered is the patients' right to access to HIV treatment, and the barriers to treatment that people face if they are migrants or from socially excluded groups such as injecting drug users.

One weapon that those fighting HIV long for is an effective vaccine, and researchers outline the scientific and policy challenges of developing an HIV vaccine. The issue of paediatric HIV/AIDS cases is also discussed.

This review, although aimed primarily at a scientific audience, is a clearly written account of how HIV is believed to have evolved over the past 40 or so years since its spread to humans from apes. The authors argue for the importance of widespread monitoring of how HIV continues to change genetically, as it moves from person to person and within infected individuals, so as to help control drug resistance and design effective vaccines against HIV.

Based on data from 28 interviews among scientists, this commentary describes in clear terms how the health biotechnology industry is thriving in South Africa, nurtured by a confidence among scientists that arose originally with the development of mining and arms industry during the apartheid regime. With the emphasis on serving local needs, particularly the development of new drugs and vaccines for HIV/AIDS, South Africa is providing a shining example of how other developing countries can follow suit.

This Commentary describes the increasing ethical dilemmas now being faced by researchers in areas with high incidence of HIV/AIDS, as they investigate immune responses to non-HIV/AIDS diseases such as malaria. Studies of immune responses require an HIV test to check whether the research volunteer is likely to have impaired immunity, which means that clear ethical guidelines are now needed to govern whether or not such research programmes need to include provisions for voluntary counselling and testing, and other services for HIV/AIDS treatment and care.

With over 350 vaccine candidates against 88 different pathogens, including HIV, now in development in academia and industry, this commentary, written for a broad audience, provides a broad overview of the current trends that will determine which candidates are most likely to reach the poor in developing countries. These include obstacles such as poor vaccine coverage with existing vaccines and a skewing of the vaccine industry away from producing vaccines against diseases that predominantly affect poor developing nations, and new organisations, funding initiatives and incentives, such as public private partnerships, that are now helping to overcome these obstacles.

This commentary outlines in clear terms the justification for making antiretroviral drugs accessible on a large scale in developing countries, noting particularly that antiretroviral drugs are now affordable, available, and cost-effective when provided in conjunction with prevention measures, and that viral resistance can be controlled.

This review puts the HIV/AIDS epidemic into perspective against other new and re-emerging diseases that have raged among human populations since the beginning of agriculture around 10,000 years ago, including SARS, bovine spongiform encephalopathy (BSE)/variant Creutzfeldt-Jakob disease (vCJD) and Nipah fever, and old diseases such as tuberculosis and cholera. The authors argue that with a better understanding of how the emergence of such diseases is governed by changes in human ecology – such as movement, environment, living conditions and social interactions – we may be in a better position to anticipate when and where there is a risk of another new disease appearing.

This short online review aimed at non-specialists summarises the current status of microbicides research, describing in clear and concise terms the different types of microbicides currently in clinical trials, how they act, and their potential shortcomings. It refers to the increasing political and financial support that the microbicides field has gained recently, not least because of the lack of an effective HIV vaccine, but also points to the need for further developments to ensure the long-term success of microbicides as HIV prevention tools, including better ways of ensuring adherence to use.

Launched to coincide with the 2004 International AIDS Conference in Bangkok, in this strategy document, the IAVI outlines plans to strengthen and expand the research and development pipeline of candidate HIV vaccines, and engage as partners those countries most affected by HIV/AIDS. Future scientific strategy includes focusing on vaccines that trigger neutralising antibodies, and understanding how live weakened vaccines work in animal models for clues to what is needed in a vaccine for protecting people.

In response to controversy over a trial in Cambodia that was halted earlier this year, this document, written for a broad audience, addresses a range of issues regarding tests of the antiretroviral drug tenofovir in healthy uninfected individuals. The clinical trials, taking place in Africa, Asia and the Americas, aim to see whether Tenofovir can protect against HIV infection in those who are at high risk of exposure to the virus — so-called Pre-Exposure Prophylaxis, or PREP. But its use raises a whole set of concerns regarding its potential impact on trial volunteers and their communities, including the prospects for encouraging drug-resistant strains of HIV to emerge and higher risk sexual behaviour.

This collection of 43 essays is by people involved in HIV/AIDS research, community education, clinical trials and advocacy, and aims to both inform and encourage global action. Written in an easy-to-read style, it introduces many of the major scientific, policy, social, ethical and economic challenges of developing an AIDS vaccine, with chapters covering issues such as HIV vaccine science, vaccine safety, ethics of clinical trials, informed consent, community action to encourage HIV vaccine development, and sources of information and help. Notable contributions from developing country authors include the personal experiences of a vaccine scientist involved in establishing the first HIV vaccine trials in Uganda, the vulnerability of women to HIV/AIDS in India , and the challenges of recruiting women to participate in clinical trials in Kenya. Illustrations include photographic accounts of the HIV virus and its life cycle, and clinical and laboratory tests on clinical trial volunteers.

This news feature aimed at a broad scientific audience likens the perplexing task of trying to develop an HIV vaccine to “flying without a compass”. HIV poses unique challenges, including its infinite variability and protective coating that masks it from antibodies, yet researchers have evidence from both human and animal studies suggesting that it may one day be possible to trigger an immune response that protects against infection.

This clearly written perspective aimed at a broad audience is from HIV/AIDS researcher David Ho of the Aarron Diamond Research Centre. He applauds the goals of the newly launched Global Vaccine Enterprise for the creation of an HIV vaccine, but raises the general concern that the kind of scientific breakthrough that will be needed to make such an enterprise successful is likely to come from ‘curiosity-driven’ fundamental research, and that safeguards need to be in place to prevent the stifling of individuals and small teams working outside of the Global Vaccine Enterprise.

This is the first publication outlining the scientific strategy of the Global Vaccine Enterprise, the most ambitious vaccine research programme ever undertaken with the goal of overcoming the enormous scientific and other challenges in the development of an HIV vaccine. Among the goals being set is the need for better coordination and transparency among researchers and organisations involved in HIV vaccine research, standardisation of laboratory and animal tests to enable different vaccine candidates to be compared and prioritised for further development, and the setting up of national research centres in countries of high HIV incidence, particularly in Africa, South America, India and the Caribbean.

This report from the US-based National Bureau of Asian Research takes an unusual look at the HIV/AIDS situation in the Muslim world, highlighting the poor surveillance and inadequate knowledge of the extent of HIV/AIDS. The Muslim world encompasses more than 30 countries across Europe, North Africa and Asia, and consists of more than one billion people. The same behaviours that are responsible for fuelling the spread of HIV/AIDS elsewhere also exist in the Muslim world — pre-marital sex, homosexuality and intravenous drug use. But many countries with predominantly Muslim populations continue to deny that such behaviours occur, and do not support surveillance or prevention efforts, with the notable exceptions of Iran and Bangladesh.

As treatment for HIV/AIDS scales up worldwide in the World Health Organization’s '3 by 5' campaign, there is a danger that prevention efforts may be neglected, which in the long term will make treatment goals far more costly, as the number of new infections continues to spiral upwards. This paper, aimed at a broad readership, presents the results of mathematical modelling different scenarios, in which treatment and prevention efforts are used either alone or together, to demonstrate that scaling up both treatment and prevention together will have far greater impact on the future course of HIV/AIDS.

A subsequent piece explains further how prevention services can be made more accessible when combined with treatment, for example the availability of treatment can encourage more people to come forward for HIV testing and counselling, which in turn can help to identify vulnerable people in need of interventions, and reduce high risk behaviour and the chance of infection spreading from person to person.

The UK-based AIDSMAP website contains news and other information on the transmission of HIV from mother to child, and its prevention. This includes the HIV and AIDS Treatment in Practice (HATIP) newsletter, issues 11, 24 and 29, which outline key approaches to the prevention of MTCT including the timing and choice of antiretroviral drug treatment, and the need for a focus on research to minimise transmission during breastfeeding.

In this editorial, Hoosen Coovadia comments on studies assessing the effectiveness of using two antiretrovirals to reduce MTCT transmission, and the effect of giving highly active antiretroviral therapy to mothers with vulnerable immune systems.

In this article Fitzgerald and M-T Behets outline four incidents that arose while conducting HIV clinical research with women in African and Caribbean countries to illustrate the "massive ethical challenges for researchers in HIV prevention trials". The cases include an HIV-positive husband refusing to use condoms with his HIV-negative spouse, cervical cancer being identified within a country which did not have the facilities to treat it, and the fatal consequences of one participant seeking an illegal abortion and another delaying surgical removal of a dead foetus on the advice of a traditional attendant and a lack of funds for treatment.

The authors note that much HIV research will involve women of reproductive age, particularly that focussed on preventing mother-to-child transmission of HIV. The four cases discussed outline the issues that can arise when research is being conducted among vulnerable women without access to basic medical services, where physical and sexual violence against women is relatively common and social injustice is widespread. In such circumstances the authors ask what responsibilities researchers have to participants who have built up a trusting relationship with them over time. They conclude that meaningful discussion between researchers and relevant communities is required, leading to a participatory research model in which potential participants and community members are involved in study design and implementation.


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This issue of the quarterly magazine from the Alliance for Microbicides Development is a special report from the international microbicides conference held in London in March 2004. Written for a broad readership, it provides an excellent overview of the state of microbicides research today, with accounts of individual presentations and cross cutting themes. Much of the work has yet to be published in the formal literature, making this a unique resource.

Following the structure of this biannual event, the report reveals the considerable progress being made in laboratory and animal studies of new microbicide candidates. Along with a better understand of how HIV infects the body following sex, is the growing realisation that different microbicides will need to be combined in a single formulation in order to block the many different ways in which HIV gains entry into the body. Researchers are also trying to develop better animal models that more closely reflect the infection process, and to test whether there is any risk of individual microbicides making infection more likely.

There is also a greater appreciation of the importance of having microbicides that treat sexually transmitted diseases other than HIV (as a means of reducing the risk of HIV infection), and the need to better understand the biology of HIV infection in the rectum following anal sex. Underlying this, behavioural studies are indicating that anal sex is a more frequent practice among heterosexuals than previously thought, as a means of birth control and preserving a woman's virginity. The report also features the highlights of discussions on the design of clinical trials, and the ethical guidelines that need to be established.