![[Feedback]](/icons/banner/feedbackACT.gif){kind=icon}
![[For Subscribers]](/icons/banner/subscriberACT.gif){kind=icon}
![[Archive]](/icons/banner/archiveACT.gif){kind=icon}
![[Search]](/icons/banner/searchACT.gif){kind=icon}
![[Contents]](/icons/banner/tocACT.gif){kind=icon}
|
|
|
|
|
||
National Institute of Nutrition, Hyderabad, India
2To whom correspondence should be addressed. E-mail: vinodinireddy{at}hotmail.com.
 |
ABSTRACT |
|---|
 TOP ABSTRACT INTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
KEY WORDS: • vitamin A • IVACG • history
|
INTRODUCTION |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
|
EARLY EFFORTS TO DEVELOP VITAMIN A INTERVENTIONS |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
|
ORIGIN OF IVACG |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
|
ORGANIZATIONAL STRUCTURE AND FUNCTIONS |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
IVACG provides technical guidance to policy makers and program managers through state-of-the-art publications on VADD. These include task force reports and policy statements on specific issues. IVACG collaborates with international organizations such as WHO and UNICEF in developing and establishing policy guidelines for the diagnosis, treatment, and prevention of VADD.
|
PAST ACHIEVEMENTS |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
, and publications are listed in Table 2
. Most meetings have been held in countries where VADD are prevalent. This helped generate local interest and support for country programs and facilitated attendance by regional scientists and policy makers and those involved in programs in VADD control. In the early years, IVACG meetings were small, with 30–40 invited participants focusing on scientific research. Today the meetings are 20 times larger, address both research and programmatic concerns, and have open and diverse participation. Highlights of the meetings and IVACG’s contributions are presented below.
|
|
During the initial decade, attention focused on xerophthalmia and blindness, which was known to be a serious public health problem in countries of Southeast Asia. The experts that gathered at the inaugural meeting in New York (1975) felt the need to provide detailed guidelines on assessment of vitamin A status, selection of intervention strategies and research needs. Three task forces were set up for that purpose and their reports were discussed at the next meeting in Haiti (1976). These topics were published as an IVACG monograph entitled Guidelines for the Eradication of Vitamin A Deficiency and Xerophthalmia.
Laboratories engaged in vitamin A analysis used different methods, and the group felt the need to consider establishing a reference laboratory, but this did not materialize. However, IVACG addressed the issue at a number of meetings and published a monograph, Biochemical Methodology for the Assessment of Vitamin A Status.
The 1978 meeting in Rio de Janeiro reviewed the draft document prepared by a task force on recent advances in the metabolism and functions of vitamin A, which was published as an IVACG monograph. The 1979 meeting in Cebu, Philippines, discussed the available methodologies for combating VADD including food-based approaches, an area that received little attention in the earlier meetings. The next meeting (1980), held in Jakarta, was jointly sponsored by WHO, UNICEF, Helen Keller International and IVACG as a global follow-up to the 1974 Jakarta meeting. WHO Technical Report Number 672, Control of Vitamin A Deficiency and Xerophthalmia, updated WHO Technical Report Number 590, which followed the earlier Jakarta meeting.
The meetings in Kenya and Senegal in the early 1980s, which focused on the situation in Africa, contributed to the growing awareness that blindness associated with malnutrition and measles was a serious problem in the region. Timing of the next meeting at WHO Headquarters in Geneva (1984) was of considerable importance in view of the resolution adopted by the World Health Assembly urging all member states to give high priority to the prevention and control of VADD.
The Hyderabad meeting in 1985 was of special significance as IVACG completed its initial decade. Discussions focused on the interactions of vitamin A and infection and childhood morbidity and mortality. A number of studies provided evidence for the role of infection in aggravating VADD. The Indonesian experience drew attention to the potential role of VADD in child mortality, which led to a proliferation of randomized controlled trials. Progress made in the first 10 years is documented in detail in A Decade of Achievement: The International Vitamin A Consultative Group (IVACG) 1975–1985, an excellent review by Donald McLaren, a founding member of IVACG.
Themes of IVACG meetings: 1990s
Beginning in 1991, it was decided to structure each meeting around a specific theme and to publish the meeting reports. The theme for the Ecuador meeting in 1991, "Community-Based Interventions," stimulated the participants to consider VADD in a broader context as a nutrition problem linked to the community’s social and economic status. The theme of the next meeting in Tanzania, "Toward Comprehensive Programs to Reduce Vitamin A Deficiency, " encouraged discussions of what it takes to move from a project to a program and how vitamin A interventions can be integrated with other health interventions. This was seen as a turning point, because the emphasis shifted from technical feasibility to sustainability. "Two Decades of Progress: Linking Knowledge to Action" was the theme of the 1994 meeting in Thailand. The objective was to strengthen the links between science and action.
Vitamin A prevention activities accelerated during the 1990s, as the World Summit for Children and the International Conference of Nutrition set new micronutrient goals, including elimination of vitamin A deficiency by the year 2000. Many countries had designed (and some had launched) national programs of mixed interventions, including vitamin A supplementation and food-based approaches, to achieve the goal. However, there were obstacles to overcome. These formed the basis for the theme of the Guatemala meeting (1996) "Virtual Elimination of Vitamin A Deficiency: Obstacles and Solutions for the Year 2000." The next meeting in Cairo (1997) focused on long-term strategies for "Sustainable Control of Vitamin A Deficiency." The importance of other micronutrients and their interactions with vitamin A were becoming increasingly recognized. The theme of the Durban meeting (1999) was "Vitamin A and Other Micronutrients: Biologic Interactions and Integrated Interventions." Thus, the meeting themes offered an opportunity to push the field ahead by setting a goal for researchers and program managers.
Vitamin A and mortality
The vitamin A agenda changed over the years. Community-based, randomized trials from Indonesia and hospital-based measles treatment trials in Africa shifted the focus from xerophthalmia and blindness to systemic effects of morbidity and mortality. Subsequent supplementation trials were presented at the Ecuador meeting (1991). Two controlled trials conducted in Nepal showed a 25–30% reduction in mortality among children receiving vitamin A supplements, whereas two reports from India and Sudan showed no significant effect. A candid debate ensued about the study design and population characteristics, which led to more controlled studies. Additional data presented at the Tanzania meeting (1993) confirmed mortality reduction when vitamin A status was improved through supplementation or fortification programs, although there were variations among communities in the extent of the impact. Based on these data, IVACG issued a policy statement highlighting the importance of adequate vitamin A status for child survival.
Thus, IVACG has played a vital role in stimulating research and providing data necessary for policy decisions. Morbidity trials from Ghana and Brazil, presented at a later meeting, confirmed that improving vitamin A status can reduce the severity of diarrhea and measles, reducing case fatality. IVACG promptly released Policy Statement on Vitamin A, Diarrhea, and Measles (1996), recommending vitamin A supplementation as an important strategy to lessen the consequences of these diseases. Thus, supplementation has become an integral component of child survival programs in many countries.
At the 1997 meeting in Cairo, attention was drawn to maternal night blindness and the associated health risks. A large-scale field trial in Nepal showed a significant reduction in pregnancy-related mortality in women who received weekly supplements of vitamin A or ß-carotene, emphasizing the importance of adequate vitamin A status for improving maternal health and survival. In other countries, interested groups met to discuss the design of additional studies to confirm these results.
Assessment methods
Several methods are available for assessing the vitamin A status of individuals and communities, including dietary, clinical, functional and biochemical indicators. A critical review of these methods at the Ecuador meeting (1991) delineated the advantages as well as the limitations of each method.
Presentations at the Guatemala meeting (1996) reminded participants that dietary assessment can help identify major sources of vitamin A in the diet and evaluate the changes in their consumption after educational intervention, but it does not establish vitamin A status. In this context, attention was drawn to the limitations of the existing food composition tables based on outdated laboratory methods and differential bioavailability of dietary carotenoids. These discussions stimulated further studies on food composition and bioavailability.
Clinical indicators in children are widely used in community surveys. Reports from Nepal showed that maternal night blindness is a useful indicator of vitamin A deficiency in pregnant women. Attempts were also made to develop simple methods to detect impaired dark adaptation, which is an early functional abnormality. Serum retinol is the most commonly used biochemical indicator of vitamin A deficiency. A study presented at the Durban meeting demonstrated that it might be possible to estimate retinol concentration in finger prick blood samples with a filter paper technique. A relative dose-response assay was suggested for measuring vitamin A stores. This was further modified (modified relative dose-response assay) to increase feasibility by eliminating one of the two blood draws. Thus, IVACG played an important role in facilitating discussions and comparing various methods, which led to refinement of techniques and development of simple methods that can be applied in the field.
Intervention strategies
The three major approaches to combat vitamin A deficiency are vitamin A supplementation, food fortification and dietary diversification. Key issues related to these interventions have been discussed at many IVACG meetings.
Vitamin A supplementation. A review of supplementation programs revealed that the coverage was often inadequate. Analysis of the national programs in India and Bangladesh presented at the Tanzania meeting (1993) suggested that vitamin A delivery is more sustainable if it is well targeted and integrated with other health care programs. The Expanded Programme on Immunization (EPI) offered a good opportunity to deliver vitamin A. Linking vitamin A distribution with measles immunization increased the coverage significantly. The success of integrating vitamin A supplementation with national immunization days was also presented at this meeting, and others were encouraged to adopt this approach. Two IVACG reports providing guidelines on vitamin A distribution with EPI contacts were published in 2000.
The other issue related to vitamin A supplementation is its safety in young infants. A clinical trial in Bangladesh raised concern by reporting bulging fontanel in a significant proportion of infants receiving vitamin A along with diphtheria-pertussis-tetanus immunization. However, a follow-up study reported at a later meeting allayed these fears, because the infants showed no long-term developmental sequelae. The new information derived from these investigations and practical experience was used to revise the earlier report Vitamin A Supplements: A Guide to Their Use in the Treatment of Vitamin A Deficiency and Xerophthalmia, published by WHO in 1988.
Vitamin A fortification. Food fortification offers a direct and effective way to correct vitamin A and other micronutrient deficiencies. The 1996 meeting in Guatemala reviewed sugar fortification programs in Central America. Various aspects of fortification including stability, quality control and monitoring were discussed. Results of a national survey in Guatemala reported at a meeting in Durban (1999) showed a high prevalence of VADD in children <3 years old, despite successful implementation of the fortification program. This showed that fortification of a single food might miss an important subgroup and therefore does not ensure adequate vitamin A status of the entire population. Fortification of complementary foods targeting young children was suggested as an alternative strategy. Vitamin A fortification of other foods like margarine in the Philippines, monosodium glutamate in Indonesia and cooking oil in India were also reviewed at that meeting. Selecting an appropriate vehicle and an adequate level of fortification to meet the requirements was emphasized.
Dietary diversification. In recent years, dietary diversification has received increasing attention as a potential long-term sustainable solution. IVACG meetings in the early 1990s reviewed the data on availability and consumption of vitamin A–rich foods, particularly plant foods that form a major source of the vitamin. The data showed that low consumption of vegetables and fruits was due to lack of awareness and low availability of these foods at the household level. This led to a number of projects promoting the production and consumption of carotene-rich foods through home gardening and information, education and communication strategies. The report Nutrition Communications in Vitamin A Programs: A Resource Book was published in 1992. The results of the gardening and nutrition communication studies presented at the Cairo meeting (1997) demonstrated the feasibility and effectiveness of increasing consumption by these approaches. A task force was set up to review these methods.
Whether increasing dietary consumption of ß-carotene–rich vegetables could improve vitamin A status remained an important question. A study presented at the 1994 meeting in Thailand showed no change in serum retinol levels of Indonesian women who received vegetable supplements, which raised questions about the bioavailability of plant carotenoids. There was an active debate on this topic, leading to further studies to identify various factors influencing bioavailability and to promote appropriate methods of preparation to retain carotene. The task force report The Bioavailability of Carotenoids: Current Concepts, published in 1999, highlighted newer approaches that allow better estimates of the vitamin A content of diets.
|
FUTURE CHALLENGES AND OPPORTUNITIES |
|---|
|
TOPABSTRACTINTRODUCTIONEARLY EFFORTS TO DEVELOP...ORIGIN OF IVACGORGANIZATIONAL STRUCTURE AND...PAST ACHIEVEMENTSFUTURE CHALLENGES AND... |
|---|
IVACG needs to continue its practice of turning the spotlight on issues of greatest relevance, stimulating research, encouraging critical discussions of new discoveries and ensuring translation of these discoveries into policy options and practical application.
Future efforts should focus on assessment of marginal VADD and their consequences and address questions related to the broad array of interventions.
Because VADD often coexist with other micronutrient deficiencies, coordinated efforts are needed to address these problems, integrating assessment and interventions where feasible. IVACG should strengthen its linkages with comparable organizations that deal with other micronutrients, for better coordination and stimulate research related to the implications and optimal means of control.
The coming years should witness more effective intervention strategies. Vitamin A deficiency must be seen within the broader context of malnutrition that afflicts the poor, and greater emphasis should be placed on integrated and multisectoral strategies, taking into account a community’s overall needs for social, economic, and ecological development.
In summary, despite the progress achieved in the past, many challenges lie ahead. IVACG should gear itself to meet these challenges and accelerate efforts to eliminate vitamin A deficiency.
|
ACKNOWLEDGMENTS |
|---|
|
FOOTNOTES |
|---|
3 Abbreviations used: EPI, Expanded Programme on Immunization; IVACG, International Vitamin A Consultative Group; UNICEF, United Nations Children’s Fund; USAID, U.S. Agency for International Development; VADD, vitamin A deficiency disorders; WHO, World Health Organization.
This article has been cited by other articles:
|
|
 |
|
  A. Sommer and F. R. Davidson Assessment and Control of Vitamin A Deficiency: The Annecy Accords J. Nutr., September 1, 2002; 132(9): 2845S - 2850. [Abstract] [Full Text] [PDF]
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
