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L. Å. Hanson
Mode of perinatal transfer of HIV-1
With the spread of the human immune virus I (HIV-1), it is becoming increasingly common for pregnant women to be infected (table 1). As a result of perinatal transmission, the number of infected offspring is consequently also increasing. Three possible routes of perinatal transmission have been considered.
TABLE 1. HIV-1 antibody-positive pregnant women, 1986-1987 (percentages)
| Kenya | 2 |
| Malawi | 2 |
| Zaire | 8 |
| Zambia | 12 |
| Uganda | 14 |
| New York City | |
| high-risk group | 10-60 |
| overall | 2-4 |
Source: A. Nahmias, personal communication.
In most instances the infection is presumably transmitted in utero. This conclusion is supported by a short incubation time after birth in some cases [1], a high incidence of hepatosplenomegaly and low birth weight [2], and the presence of foetopathy in children with acquired immune deficiency syndrome (AIDS) and AIDS-related complex (ARC) [1]. The dysmorphic features suggest exposure to the virus in the first trimester of pregnancy [1]. Isolation of HIV-l from a 20-week foetus [3], detection of HIV-1 in cord blood [1, 4] or within 24 hours of birth [5], and demonstration of the virus in infants delivered by caesarean section [6] are also taken as evidence. A second possible route of transmission is the contact of the neonate with infected blood from the mother at delivery.
Finally, consideration is being given to the possibility that breast milk can transfer HIV-1. The virus has been isolated from the cell-free clear middle layer from centrifuged milk from three seropositive mothers [7]. The cells in the milk could not be cultured for the virus because of bacterial contamination. The possible role of antibodies present in milk for infectivity of the virus or for its detection has not been studied. The capacity of the virus to infect by way of the intestinal tract, reaching its receptors on T4 cells, is not clear. However, about 15% of the many intra-epithelial lymphocytes in the gut mucosa are T4 cells.
It should be noted that human milk contains significant numbers of leukocytes. They reach a maximum three to four days after the onset of lactation, with from 500,000 to 10 million cells per millilitre. By four to six weeks after parturition, they are present at less than 100,000 per millilitre. The number of lymphocytes declines sharply within two to three days postpartum, whereas the number of macrophages declines less and remains at detectable levels. With increasing milk volumes they continue to be present [8]. It is likely but not yet demonstrated that such milk cells may be infected with HIV-1.
Only one case of transfer of HIV-1 from mother to baby has been published in which the transmission could have been through breast milk [9]. The mother was infected by a postpartum blood transfusion, and her infant became seropositive either due to the six weeks of breast-feeding or by some other close contact with the mother. Four other cases, from Rwanda and Zaire, not yet published, also suggest breast milk as the mode of transmission.
No definite data exist as to the relative frequency of different modes of transmission of HIV-1 from mother to offspring. Among 104 children in the United States with AIDS who were studied for disease transmission, the risk factors were as follows, in order of frequency: maternal risk factors, paternal risk factors, sexual abuse, and exposure to needles at home [1]. The majority were children of intravenous-drug-abusing mothers and/or fathers or children of bisexual fathers.
Although intrauterine infection from the mother may be most common, Chiodo et al. have described 12 babies from HIV-1 seropositive mothers, of whom 3 of 7 delivered normally became infected, but none of the 5 delivered by caesarean section did [10]. This could be taken to suggest that natural delivery increases the risk of perinatal transfer, but the matter certainly needs further study.
The risk for babies of seropositive mothers of developing ARC or AIDS varies according to different sources, with figures ranging from 15% to 50% for the first child and from 60% to 80% for later siblings [1; A. Nahmias, personal communication]. Only one of a pair of identical twins was infected in one instance [1]; the healthy twin was followed for 10 months.
The risk of transfer of HIV-1 in breast milk
Few cases are known in which breast milk can have transferred HIV-1. Yet the risk cannot be discounted, and countries such as the United States [11] and Sweden are advising seropositive mothers not to breast-feed. It is also advised that human-milk banks should pasteurize their milk [12, 13]. Such advice can be followed in places where diagnostic tests for HIV-1 infection are readily available and where pasteurization can be arranged. In such areas it is likely that the risk of contracting various gastro-intestinal and respiratory-tract infections is limited, and decreased frequency of breast-feeding may not have disastrous effects.
The problem is much more serious, however, in areas where such infections are frequent and breast-feeding is very important in protecting against them. A recent estimate of mortality from various diseases in east Africa shows that approximately one person dies of AIDS in large cities for every 10 who die of diarrhoea, but in rural areas the proportion is only one death from AIDS for every 4,000 deaths from diarrhoea [14], This illustrates the complexity of the problem. It might be added in this connection that the median relative risk of diarrhoea mortality is estimated to be about 25 times as high in non-breast-fed as in exclusively breast-fed infants.
With the limited information presently available concerning the risk of transfer of HIV-1 through breast milk, it seems of prime importance to propose research that can expand our knowledge. Specifically, it is important to determine whether or not those at risk of being infected through milk have not already been infected in utero. Any recommendations concerning breast-feeding in relation to AIDS must be provisional and temporary until additional information appears. It should be realized that today the mortality of infants from AIDS is still minimal compared to that from conditions such as diarrhoea. Diminished breast-feeding would make that difference even more striking .
References
Maarten D. C. Immink
This paper offers some ideas for the establishment of community-designed, -operated, and -evaluated food and nutrition surveillance systems, in support of food security of the poor and bottom-up planning processes for socio-economic development in Central America. Current social processes are opening up opportunities for the poor to play a greater role in solving poverty problems and to contribute to their own food security. Community-based food and nutrition surveillance systems should be seen as an instrument of socio-economic development.
The current state of food and nutrition surveillance in Central America
The predominant current view in Central America regarding food and nutrition surveillance is that its main purpose is policy and programme advocacy in relation to improving the nutritional status of low-income populations. What have been explicitly identified as food and nutrition surveillance activities have largely been confined to the health sector, using health and nutritional status indicators for the identification of population groups at some degree of risk of undernutrition. Recently, macro-level tools such as food-balance sheets and basic-food-basket analysis have also been considered as relevant instruments of food and nutrition surveillance.
Under the aegis of a regional and EEC-supported food-security programme, efforts are being initiated in some countries to integrate sectoral information systems into a public-sector network in support of food-security activities. Much of the recent technical discussion among public-sector agencies has centred on organizational structures, indicators to be generated, and needed infrastructures for data processing and analysis. What has been largely absent from these discussions is a careful consideration of the use of surveillance data, and of the mull-functional dimensions of food and nutrition surveillance systems as proposed by the FAO and other agencies [1].
Food and nutrition surveillance systems are seen as supporting public-sector, top-down planning processes and as a basis for sectoral actions in the form of national programmes. Information routinely or periodically generated at the community level is rarely fed back in support of local decision making and action taking. Serious operational bottlenecks at national levels related to data processing and analysis have greatly limited the effective use to which the eventually disseminated information is put. Lack of clarity in the definition of the functions of the surveillance systems and of operational concepts and implementation procedures, as well as "territorial,, concerns among public-sector agencies, have prevented the Central American countries from organizing such a system as a basis for multisectoral decision making and action taking in the short and long run. It is difficult to see how surveillance activities to date have contributed effectively to the food security of the poor in Central America.
Socio-economic development, popular participation, and food and nutrition surveillance
Socio-economic development may be viewed as the full achievement of human potentiality in both material and spiritual terms. Food security at all times is a high-priority component of socio-economic development, in fact an essential pre-condition. Food and nutrition surveillance is an operational instrument to achieve food security for all members of society, and thus an instrument of socioeconomic development.
It has been recognized for some time that popular participation is essential for development, and that development is in fact participation [2]. This idea found formal expression in 1979 in the declaration of the World Conference for Agrarian Reform and Rural Development, which stated in part: "Rural development strategies can realize their full potential only through the motivation, active involvement and organization at the grass-roots level of rural people. . . in conceptualizing and designing policies and programmes,, [2]. This focus has since then guided the development work of UN specialized agencies, and of some international and national non-governmental organizations, though often it has not been put into effective operation.
Popular participation occurs essentially in two ways. In the first, certain groups are organized in order to participate in development activities designed and operated from above, often by a public-sector agency. Participation is seen as making the outcome of the activities more effective in accordance with criteria adopted by central planners, and may consist of community members providing free labour services or material goods for development projects. The second type of participation is a bottom-up process that results in grass-roots organization and allows the poor to take major responsibility for their own development in accordance with their own perceived needs. As part of the process the poor are better equipped to formulate and express their needs and their priorities for actions, and to participate technically in designing and implementing development activities, thus over time decreasing their dependence on external technical and financial sources of development assistance.
It is my contention that there is a role for food and nutrition surveillance in fostering socio-economic development with grass-roots-level participation. This role has not yet been recognized in Central America. Economic growth is often confused with socioeconomic development, and participatory processes are only seen as necessary in order to increase the local impact of national and regional social action and development programmes. However, new social and political currents start to create space for effective community organization at grass-roots levels in support of bottom-up development activities. This is probably even more true for populations living in marginal urban areas than for the rural poor. Nevertheless, food and nutrition surveillance activities, if designed, operated, and evaluated by communities organized at the grass-roots level, can in turn strengthen development-oriented participation processes and contribute significantly to the food security of the poor and their socioeconomic development.
Such activities by the community should result in an understanding of the factors that produce food and nutrition problems and should provide a basis for self-determination and implementation of solutions in accordance with the aspirations collectively held by the community and within the broad context of socioeconomic development.
The implementation process
The following should be the principal functions of community-based food and nutrition surveillance systems:
The community should set priorities as to what basic functions should be emphasized in the initial design of the systems. For example, communities that frequently suffer from acute food shortages may wish to emphasize the system's early-warning function.
No operational blueprint is possible of community-designed, -operated, and -evaluated food and nutrition surveillance systems. Inherently, they are not necessarily duplicable, although they may coincidently have elements in common. This may be partly the result of a demonstration effect among communities that are in contact, especially those that face similar poverty problems or acute hunger conditions.
The role of external (to the community) technical assistance should be to help to create the necessary conditions so that the community can effectively manage, use, and evaluate the system. This may take the form of training community members in data recording, tabulation, and interpretation, establishing certain infrastructure for data processing and analysis, or technical assistance with the design of the system. In general, the system should be simple and flexible in design and should contemplate incorporating qualitative information, not only quantitative data. The former has the advantage of often serving more effectively as a basis for rapid decision making or action taking, especially in situations that do not allow or require in-depth study of underlying causes. The system should be flexible enough so that it can continuously be adjusted in accordance with the current data needs of the community.
The sequence of different stages of the implementation process might be as follows:
During the first stage, the community collectively thinks about and discusses its food and nutrition problems, their immediate causes, and what priorities should be given to solving them. For this process of diagnosis the community may use existing data and decide to obtain other information applying simple data-collection techniques. External technical assistance may facilitate this process. In participatory sessions the community decides on courses of actions and sets priorities. Identifying and assigning priorities to problems and courses of action constitute the bases for identifying information needs, and thus for the design of the information system. At this stage external technical assistance may be required in the forms of training of community members, technical help with validation of the system, infrastructure, etc. Once the system is operational, it should be evaluated continuously by the community. For this purpose, some operational indicators should be included that will allow the system's performance to be monitored as a basis for making adjustments over time.
Conclusions
Community-designed, -operated, and -evaluated food and nutrition surveillance systems should not be seen as the only information systems in support of national food security. Decision making and action taking in relation to food security and socio-economic development take place at different levels and require information at those levels, including macro-level information and data obtained at the community level and integrated at aggregate levels (e.g. , local, regional, national). But in Central America, as in other parts of the developing world, food and nutrition surveillance should not be limited to supporting top-down processes of decision making and action taking related to food security and socio-economic development. In view of the diminishing capacity of the public sectors to provide technical and financial solutions to poverty problems, there is an increasing need for the poor to be able to determine and take responsibility for their course of development.
Once operational, the surveillance systems are likely to be effective because they allow firm integration of information-generating activities with decision making and action taking; they may strengthen community organization at the grass-roots level, which in turn will aid the social development process; they increase the effectiveness of external resources in contributing to the community's food security and socio-economic development; and they mobilize community resources in a more rational way.
The firm integration of information-generating activities with decision making and action taking ensures that the information can be transformed rapidly into decisions, and that it is appropriate and leads to actions that are relevant to local conditions and in accordance with the aspirations and priorities established by the poor themselves.
Community organization does not take place in a vacuum. It is generated as a need and often constitutes a pre-condition for taking actions. To the extent that these systems serve as a catalyst for strengthening community organizations at the grass-roots level, they contribute also indirectly to the social development process by making other actions at the community level more effective, whether undertaken with external or community-based resources. The community becomes better equipped to define what resources are needed in accordance with the priorities with which actions are to be taken, the timing of resource use, etc., thus increasing their impact. Depending on the process by which they are designed and operated, surveillance systems can be instruments that allow the communities to understand their own reality and thus take greater responsibility in charting their own development course.
References
Marylou L, J. Mertens and Gretel H. Pelto
Introduction
The purpose of this statement is to express the need for training programmes explicitly designed to improve the quality of social-science inputs into nutrition and health research and programme activities.
From a variety of sources, including the expanding body of data on the sociaI epidemiology of nutrition and studies of the social correlates of dietary practices as well as the experiences of health-care and nutrition professionals, the role of socio-cultural and behavioural factors in the aetiology of nutrition problems and their solution is becoming increasingly more evident. Nutrition has always been a multidisciplinary field, drawing concepts and techniques from other natural sciences, including physiology, biochemistry, molecular and cellular biology, and medicine. Indeed, the common practice of naming a university unit devoted to nutrition a "Department of Nutritional Sciences,, reflects the multi-sectoral nature of the enterprise. Recognition of the social components of nutrition has led to the need to cast a still wider net, bringing social-science concepts and methods into the investigation of nutrition issues and nutrition-policy implementation.
One important vehicle by which new methods and theoretical perspectives are introduced into a field is through collaborative research activities. The expansion of the multi-disciplinary team of nutrition investigators to include anthropologists and other social scientists is a logical and timely extension of biological investigation. Including social scientists in the development and implementation of nutrition and health programmes would bring a social perspective to bear on direct problem-solving activities.
There are, however, a number of serious barriers to effective collaboration. One of the most important is the scarcity of social scientists with the requisite background, training, and professional situations. Throughout the world, in both industrialized and developing countries, nutrition and health-care projects have found it difficult at best, and often impossible, to develop appropriate working relationships with social scientists. To a large extent, this situation reflects the orientations and traditions of training and research in the social sciences. For example, in anthropology, attention to issues of contemporary health and nutrition, particularly in applied contexts, has Only recently begun to attract serious attention. Moreover, the lack of experience in quantitative methods makes it difficult for traditionally trained anthropologists to collaborate with bio-medicaI researchers.
The professional circumstances and expectations that social scientists face is another barrier. Typically, most anthropologists are employed in universities, where administrators are reluctant to encourage their staff members to participate in projects that take them away from their academic pathways. Promotion and job security are tied to academic publications in the primary discipline, rather than to applied, multidisciplinary, problem-solving research. Positions outside academic settings have only recently become viable alternatives, and they rarely carry the same job security and opportunities for professional development that one finds in a university.
Social organization and attitudes within the biomedical and nutrition community are another source of the problem. Too often, social scientists find themselves in a low status position compared to comparably trained big-medical colleagues. Lack of understanding about the nature of social-science concepts and methods and unfamiliarity with the language and vocabulary lead to misunderstanding, charges of using jargon, and denigration of data quality. At the same time, social scientists often fail to appreciate the complexity of the big-medical issues and are unable to communicate directly about the central issues of concern to biological researchers and clinicians.
Despite their prevalence and historic depth, none of these barriers are irremediable, and ail of them need to be addressed. Education and training programmes are central to the solution. They are critical for ameliorating the "personnel crises,, due to the scarcity of social scientists with appropriate skills and interests. To some extent training programmes will also help to moderate the other barriers as well.
This report outlines several strategies for training, each of which addressees some of the needs that have emerged in recent years.
Training options
Long-term professional training
The most intensive and complete training for a professional specialization in nutritional anthropology or social nutrition occurs through a graduate programme leading to an advanced academic degree. Such a programme would draw from both nutrition and anthropology, with the student obtaining a solid educational background in both fields. As is true of any composite field, such as urban planning or social policy, certain features of a "classic education,, in the traditional academic disciplines from which the specialization emerges must necessarily be forgone. However, this does not mean that individuals trained in such programmes must be unprepared for more traditional academic or research positions as a consequence of an educational programme that prepares them to engage in multi-disciplinary research.
Post-graduate training
Specialized social-nutrition (or social-medicine) professionals can also be trained with a much less lengthy programme if the individuals are already academically prepared. The model of the "postdoctoral year" of specialized study is highly appropriate for both young professionals and older researchers who are seeking new research directions. For example, a one-year post-graduate programme leading to a certificate in nutritional or medical anthropology could be offered for social scientists who wish to become skilled researchers in this area but have little previous experience with medical and nutritional issues.
Integrated curriculum and specialized tracks
The inclusion of social-science components in the training of health-care and nutrition professionals occurs to some extent in many (if not most) professional curriculums. However, too often these subjects are seen as irrelevant, too academic, or dull by students who are eager to learn hands-on, clinical skills.
Integrating social and cultural perspectives directly into technical subject matter has proven to be a successful mechanism for overcoming these attitudes. For example, in courses in malnutrition the social and cultural factors in the aetiology of specific nutritional deficiencies can be presented together with the pathophysiology .
The establishment of a social-nutrition or social-epidemiology track as a specialized option within an MS or MPH programme is another means of increasing the level of social-science skills in big-medically trained professionals.
Short-term training programmes
Awareness-building workshops: nutritional anthropology for big-medical personnel, and nutrition for social scientists
As in all multi-disciplinary situations where individuals must communicate with new vocabulary, new concepts, and different expectations, the involvement of social scientists in nutrition will inevitably engender problems for all the participants. A modicum of familiarity with the modus operandi and basic concepts of the contributing fields is probably a prerequisite for effective collaboration.
Awareness-building workshops are intended to address this need. The purpose of workshops on nutritional anthropology for big-medical personnel is to introduce them to basic concepts and methodological orientations of anthropology and to provide a general overview of some of the key socio-cultural questions in contemporary nutrition. Similarly, workshops directed toward social scientists are for the purpose of introducing them to key methods, concepts, and issues in nutrition and to provide them with some familiarity with the vocabulary of discourse in nutrition.
Skill-development workshops
The purpose of skill-development workshops is to provide an opportunity for individuals to acquire new research techniques and capabilities. Given the short time frame of a workshop, this mode of skill acquisition is probably most useful in connection with specific, well-defined projects. Workshops can be focused on proposal development, on protocol development and data collection. on tools for data analysis, or on aspects of programme implementation.
The specific purpose of a workshop and the types of participants and project needs must dictate format and content. However, it is possible to make some suggestions about general principles to consider with regard to short-term workshops. A general framework to guide the design and organization of workshops might include the following features:
- social and biological interactions in nutrition
- the perspective of social epidemiology,
- the role of culture in relation to other social and biological factors,
- multiple levels of analysis, from the individual to household, community, and society,
- microlevel-macrolevel linkages,
- qualitative and quantitative methodologies and the linkages between these modes of data collection and analysis.
Conclusion
In view of the urgent need to develop multi-disciplinary research and programme teams to work on pressing issues of nutrition and health, and the present shortage of appropriately oriented and trained social scientists, the potential of short-term workshops should be seriously considered. Certainly short-term training alone is insufficient, and longer-term professional development opportunities must also be developed. Several different types of training and education strategies are required, and it is important for various groups - professional organizations, international agencies, academic institutions, and government agencies - to begin to address these needs.