Mother-to-child transmission of HIV through breast-feeding is the remaining challenge facing mothers in resource-poor settings with a high HIV prevalence. Nearly all infants in developing countries are initially breast-fed, and most children continue to receive some breast-feeding until at least 6 months of age but frequently into the 2nd year of life, especially in sub-Saharan Africa and Asia. In December 2002, international researchers convened in Ghent, Belgium, to discuss mechanisms for, rates and risk factors of, and approaches to prevention of HIV transmission through breast-feeding. Four papers were compiled bringing together the presentation and discussions during this workshop, while the fourth paper also benefits from presentation made during an earlier workshop on vaccines in the prevention of mother-to-child transmission. These papers summarize the current state of knowledge and highlight the outstanding issues that will need to be addressed in the very near future before research advances can be translated into public health practice.
An estimated 800,000 children are newly infected with HIV annually. The majority of these children live in sub-Saharan Africa, where half of HIV-infected children die before their 5th birthday, and HIV is already contributing to increased childhood mortality rates overall. Nearly all infants in developing countries are initially breast-fed, and most children continue to receive some breast-feeding until at least 6 months of age but frequently into the 2nd year of life, especially in sub-Saharan Africa and Asia. Prolonged breast-feeding by an HIV-infected mother doubles the overall risk of mother-to-child transmission of HIV from <20% to as much as 40%. With the considerable risk of acquisition of HIV infection through breast-feeding, reduction of HIV transmission during the breast-feeding period is one of the most pressing public health dilemmas confronting researchers, health care professionals, health policy makers, and HIV-infected women in many areas of the world. HIV and infant feeding is an important public health issue, particularly in regions where HIV prevalence is high and infectious diseases and malnutrition are the leading causes of childhood death.
In December 2002, international researchers convened in Ghent, Belgium, to discuss mechanisms for, rates and risk factors of, and approaches to prevention of HIV transmission through breast-feeding. An overview of existing knowledge relating to postnatal transmission of HIV infection through breast-feeding was provided in presentations covering risk factors for transmission, immune defenses against breast milk transmission of HIV, virologic aspects of transmission, and viral resistance in breast milk. Interventions to prevent breast milk transmission were reviewed, including complete avoidance of breast-feeding or early weaning, avoidance of mixed feeding, preventing and treating breast pathology and infant thrush, and chemical or heat treatment of expressed breast milk. Chemo- and immunoprophylaxis studies in infant macaques provided the background for presentations on antiretroviral prophylaxis trials with antiretroviral drugs given to either the breast-feeding, infected mother or her breast-fed, uninfected infant. Finally, other approaches to prevent postnatal transmission of HIV through breast-feeding such as passive and active immunization were also discussed.
Although it is perhaps the most promising approach to the prevention of postnatal transmission of HIV, antiretroviral-based research should be viewed neither in isolation nor as a panacea. The prevention and management of maternal breast pathology, determination of the optimal timing for weaning, further assessment of the potential role of exclusive breast-feeding in minimizing postnatal transmission risk, as well as the efficacy of infant vaccines and passive immune strategies should also receive attention. Ultimately, prevention of postnatal transmission should be tailored to the individual woman's situation and be based on a combination of interventions including antiretroviral drugs. Cost-effectiveness and cost-benefit studies will then be important to assist policy makers and program planners. Irrespective of the interventions that will meet these criteria, the active promotion of exclusive breast-feeding will remain a challenge for HIV-infected women who opt to breast-feed. Finally, given the extremely high risk of infant infection associated with maternal seroconversion during lactation, approaches to prevention of breast-feeding transmission of HIV must also address ways to prevent HIV-uninfected mothers from becoming infected after delivery.
Preventing postnatal transmission of HIV via breast-feeding thus remains a scientific frontier challenging researchers in many areas of the world. The meeting held in Belgium in December 2002 by the Ghent IAS Group helped strengthen the research network and agenda of those engaged in this fight. Based on the presentations during this meeting, four review papers were prepared for all those interested in the prevention of mother-to-child transmission of HIV in resource-poor countries. The fourth paper also benefits from presentation made during an earlier workshop on vaccines in the prevention of mother-to-child transmission. These papers summarize the current state of knowledge and highlight the outstanding issues that will need to be addressed in the very near future before research advances can be translated into public health practice.
From *Centre for Paediatric Epidemiology and Biostatistics, Institute of Child Health, University College, London, UK, Ghent Working Group on HIV Infection in Women and/Children; †Inserm U 330, Institut de Sanité Publique Epidémiologie et Développement (ISPED), Universite Victor Segalen Bordeaux 2, Bordeaux, France, Ghent Working Group on HIV Infection in Women and Children; ‡Centers for Disease Control, Atlanta, GA; and §Pediatric, Adolescent, and Maternal AIDS (PAMA), National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, MD.
Received for publication June 5, 2003; accepted October 31, 2003.
Correspondence: Marie-Louise Newell, Center for Paediatric Epidemiology and Biostatistics, Institute of Child Health, University College London, UK (e-mail: firstname.lastname@example.org).
Prevention of HIV Transmission Through Breast-feeding: Strengthening the Research Agenda: Ghent (Belgium), December 12–13, 2002, The Ghent IAS Working Group on HIV in Women and Children (a meeting organized with the joint sponsorship of International AIDS Society [IAS] and Elizabeth Glaser Pediatric AIDS Foundation [EGPAF]
Scientific Committee: F. Dabis (Bordeaux, France), MG. Fowler (Atlanta, GA), M.L. Newell (London, UK), J.S. Read (Bethesda, MD), J. Safrit (Santa Monica, CA), M. Temmerman (Ghent, Belgium), C. Wilfert (Chapell Hill, NC).
Participants: R. Becquet (Bordeaux, France), K.A. Bedri (Addis Ababa, Ethiopia), D. Buyse (Kampala, Uganda), H. Coovadia (Durban, South Africa), A. Coutsoudis (Durban, South Africa), R.E. Ekpini (Abidjan, Côte d'Ivoire), T. Farley (WHO, Geneva), P. Fassinou (Abidjan, Côte d'Ivoire), P. Gaillard (Arusha, Tanzania), A. Gibbons (Washington, DC), D. Harris (Rockville, MD), J. Humphrey (Harare, Zimbabwe), E. Janoff (Minneapolis, MN), B. Jefferey (Pretoria, South Africa), G. John-Stewart (Nairobi, Kenya), S. Kanshana (Bangkok, Thailand), L. Kuhn (New York, NY), N. Kumwenda (Llilongwe, Malawi), V. Leroy (Bordeaux, France), S. Lockman (Gaborone, Botswana), C. Luo (UNICEF, Nairobi), A. Massawe (Dar es Salaam, Tanzania), D. Mbori-Ngacha (Nairobi, Kenya), J. McIntyre (Soweto, South Africa), N. Meda (Bobo Dioulasso, Burkina Faso), F. Mmiro (Kampala, Uganda), L. Muenz (Rockville, MD), J. Nkengasong (Abidjan, Côte d'Ivoire), B. Richardson (Seattle, WA), N. Rollins (Durban, South Africa), A. Ruff (Baltimore, MD), R. Ruprecht (Boston, MA), J. Shao (Moshi, Tanzania), T. Taha (Baltimore, MD), I. Thior (Gaborone, Botswana), T. Thomas (Kisumu, Kenya), P. van de Perre (Montpellier, France), C. van der Horst (Llilongwe, Malawi), K. van Rompay (Davis, CA), I. de Vincenzi (WHO, Geneva), and J. Vyankandondera (Kigali, Rwanda).