Eliminating iodine deficiency disorders the role of the International Council in the global partnership
Basil S. Hetzel1
ABSTRACT: Iodine deficiency is the most common preventable cause of brain damage. WHO estimates that some 2.2 billion people are at risk from iodine deficiency in 130 countries. A programme of universal salt iodization was established in 1994 with the aim of eliminating the problem by 2000. This paper reports progress in this field, with particular reference to the primarily scientific role of the International Council for Control of Iodine Deficiency Disorders, a nongovernmental organization founded in 1986. It is now a multidisciplinary network of 600 professionals in 100 countries.
Keywords Iodine/deficiency; Deficiency diseases/prevention and control; Nongovernmental organizations; International cooperation (source: MeSH, NLM).
Mots clés Iode/déficit; Carences nutritionnelles/prévention et contrôle; Organisations non gouvernementales; Coopération internationale (source: MeSH, INSERM).
Palabras clave Yodo/deficiencia; Enfermedades carenciales/prevención y control; Organizaciones no gubernamentales; Cooperación internacional (fuente: DeCS, BIREME).
Iodine deficiency is the most common cause of preventable brain damage. WHO estimates that 2.2 billion people are at risk in 130 countries (1). These people live in environments where the soil has been leached of iodine because of flooding in river valleys and high rainfall and glaciation in hilly areas. The deficiency in the soil leads to deficiency in all forms of plant life, including cereals. Large human populations living in systems of subsistence agriculture in developing countries are consequently affected, for instance in the great river valleys of Asia (2).
Iodine is an essential element in the chemical structure of thyroid hormones and iodine deficiency leads to a reduction in the secretion of these hormones. This is particularly important in pregnant women, who may not be able to produce the extra thyroid hormone required for normal fetal brain development in the first half of pregnancy (2).
Programmes to eliminate iodine deficiency have been established on the basis of an informal global partnership and the distribution of iodized salt. The partnership is made up of the people and governments of the affected countries, three international agencies (WHO, United Nations Children's Fund (UNICEF), and the World Bank), three bilateral development agencies (Australian Agency for International Development, Canadian International Development Agency, and the Dutch International Cooperation) that provide funding to countries, the salt industry, and Kiwanis International (a World Service Club with 600 000 members which has raised US$ 40 million for the support of country programmes through UNICEF) (3).
Since 1985 an international expert network, the International Council for Control of Iodine Deficiency Disorders (ICCIDD), has played an important, primarily scientific role in the partnership, relating to the initiation and monitoring of a global preventive programme involving the use of iodized salt. This body now has 600 members from 100 countries. They are professionals in the fields of endocrinology, nutrition, epidemiology, public health, iodine technology, education, and planning, and most are from developing countries. From the outset the members have been committed to assisting countries with their programmes, using iodized salt as the main technology. More recently Micronutrient Initiative and the Program Against Micronutrient Malnutrition have joined the Partnership as technical agencies.
The role of the International Council for Control of Iodine Deficiency Disorders (ICCIDD)
The role of the International Council for Control of Iodine Deficiency Disorders (ICCIDD)
The role of ICCIDD can be divided into the four stages that are necessary for the provision of technical support: firstly, communication of the problem as a significant factor in human development at the population level; secondly, advocacy with agencies and governments; thirdly, implementation of country programmes; and fourthly, sustaining country programmes.
The results of relevant research had to be communicated with a view to the initiation of national prevention programmes. This required a reconceptualization of the effect of iodine deficiency from the common lump in the neck (goitre) to a general effect on growth and development at population level, with particular reference to brain development. The term "iodine deficiency disorders" (IDD), proposed in 1983, has been generally adopted (4). It refers to all the effects of iodine deficiency on growth and development in human and animal populations which can be prevented by correcting the deficiency (4, 5). These effects include goitre, abortion, stillbirth, and neonatal and other types of hypothyroidism, but the major consequences are fetal brain damage of varying degrees and cretinism.
A meta-analysis was conducted of data from 18 studies in which comparisons were made between iodine-deficient populations and control populations with similar social and cultural backgrounds. The mean intelligence quotient score for the iodine-deficient groups was 13.5 points below that of the groups that were not iodine-deficient (6). The data further highlighted the major population dimension of the effect of iodine deficiency on neuropsychological development.
In relation to the development of national prevention programmes the IDD concept had to be disseminated among politicians and bureaucrats in non-technical language as well as among the wide range of professionals involved in public health programmes.
The correction of iodine deficiency brings considerable economic benefits. In humans, productivity is increased, the quality of life is enhanced and children improve their performance at school. There is increased productivity of chickens, pigs, sheep, and cattle, and the people who farm them gain financially. It is important to draw attention to these benefits when attempts are made to encourage acceptance of iodization programmes (3).
Discussions on the creation of ICCIDD were held in 1985 at a WHO/UNICEF intercountry meeting in Delhi, India. A group of 12 thyroid scientists and public health professionals, including WHO and UNICEF representatives, agreed to proceed with initial support from the Australian Aid Programme (AusAID), UNICEF, and WHO. ICCIDD was formally inaugurated with the support of WHO and UNICEF in Kathmandu, Nepal in 1986 (2, 3). Subsequent support was received from AusAID, the Canadian International Development Agency, World Bank, Dutch International Cooperation, and the Swedish International Development Agency.
In 1987, ICCIDD was recognized as the expert group on all aspects of IDD by the United Nations system through its Subcommittee on Nutrition, which established an IDD Working Group of multilateral and bilateral agencies involved in nutrition programmes. ICCIDD reports to this body. In 1994, ICCIDD was officially recognized by WHO as a nongovernmental organization working collaboratively towards the elimination of IDD (3).
Since its foundation, ICCIDD has made technical assistance to national programmes its first priority. This led to a close working relationship with governments of countries with severe IDD, usually through health ministries, and with WHO and UNICEF. The 1986 World Health Assembly passed a Resolution noting this new approach to the prevention and control of IDD (7).
In 1990 a World Health Assembly Resolution called for the elimination of IDD by 2000 (8), and in 1996 one calling for sustainability of the programme through systematic monitoring was passed (9). Both Resolutions included a reference to the role of ICCIDD and its availability to assist countries.
Iodine deficiency has been met at the technological level with the use of iodized salt (13), which was effective in a number of industrialized countries. However, in developing countries the results of this approach were generally disappointing until the previous decade. The situation changed, however, once the effects of iodine deficiency on brain development were recognized.
By 1990 an action plan for the elimination of IDD by 2000 had been developed by ICCIDD, embracing measures to be adopted at the global, regional, and national levels (10). It was endorsed by the United Nations Subcommittee on Nutrition in February 1990. In the same year the goal for IDD elimination was accepted by the World Health Assembly, UNICEF, and the World Summit for Children. The latter meeting was attended by 71 Heads of State, who signed a declaration on the provision of new goals for improved health and education for all children (11). This declaration, which was subsequently signed by representatives of 88 other national governments, has provided very important political support for national IDD programmes throughout the world.
A significant factor in the development of these national programmes has been a series of regional meetings held by ICCIDD with the support of WHO and UNICEF. They were attended by representatives of health ministries, the salt industry, the mass media, and other important sectors. They took place in Yaoundé, Cameroon, in 1987; Delhi, India, in 1989; Dar es Salaam, United Republic of Tanzania, in 1990; Tashkent, Uzbekistan, in 1991; Brussels, Belgium, in 1992; Alexandria, Egypt, in 1993; Quito, Ecuador, in 1994; Dhaka, Bangladesh, in 1995; Harare, Zimbabwe, in 1996; Munich, Germany, in 1997; and Beijing, China, in 1998.
These meetings have enabled the experts within the ICCIDD network to communicate with professionals from many countries. An additional development has involved consultancies and further contacts through ICCIDD regional coordinators, designed to identify and remove obstacles to progress. A model national programme has been presented at the regional meetings, to demonstrate its multisectoral nature and the relationships between its different elements (Fig. 1).
The ICCIDD multidisciplinary network meets the need for expertise in epidemiology, the establishment of laboratories for the determination of iodine concentration in salt and urine, planning, communication, management, and salt iodization and other iodine technologies.
On the grounds of effectiveness and cost the preferred approach is that of universal salt iodization. This means that all salt for human and animal consumption should be iodized. Legislation on this matter has been passed in 98 countries and there is draft legislation in another 12 (1). The recommended iodine level is 2040 mg as potassium iodate per kg of salt (12).
The next challenge faced by ICCIDD and its partners concerns sustainability. In the past, success has been followed by failure for various reasons. In Colombia and Guatemala, for example, political changes and social upheaval were responsible for failure. In the countries of the former USSR, complacency and apathy followed initial success.
The cooperation of the salt industry in providing iodized salt of good quality is very important for sustainability. The Salt 2000 Meeting in The Hague resolved to support the elimination of IDD. A Global Network for the Sustainable Elimination of Iodine Deficiency has been established between the salt industry, WHO, UNICEF, ICCIDD, Micronutrient Initiative, Program Against Micronutrient Malnutrition, and Kiwanis International.
Criteria for the elimination of IDD as a cause of brain damage were determined by a joint WHO/UNICEF/ ICCIDD working group in 1994. They have recently been reviewed (13). Particular emphasis was laid on the levels of iodine in salt and urine. The level of iodine in salt should be in the range of 2040 mg per kg; urinary iodine should be in the range of 100200 mg/l (12, 13). There is a vital need for monitoring of urinary iodine levels at both the higher and lower values. The higher level should not exceed 200 mg/l in order to minimize the risk of iodine-induced hyperthyroidism. The lower level is required in order to ensure the prevention of fetal brain damage during pregnancy and damage to the infant brain, particularly during the first two years of life, when it is developing very rapidly.
The term "partnership evaluation" has been adopted by ICCIDD in order to describe the independent checking of monitoring procedures and other aspects of national programmes by ICCIDD in collaboration with WHO, UNICEF, and national government representatives. Experience indicates that it is essential for the social process to continue the "wheel" must keep turning if sustainability is to be ensured (Fig. 1). The wheel model shows the social process involved in a national IDD elimination programme. Success requires the establishment of a national IDD council for elimination with full political and legislative authority to carry out the process.
As an expert scientific body, ICCIDD has been particularly important in relation to the complications associated with an increased iodine intake in iodine-deficient populations (14). The most serious complication is iodine-induced hyperthyroidism, which mainly affects older people with nodular goitres. This disorder subsides after correction of the deficiency. In 1995, ICCIDD was involved in the monitoring of an iodine-induced hyperthyroidism (IIH) outbreak in Zimbabwe following salt iodization (15). The problem subsided after three years but there was some mortality from heart complications. IIH can be minimized by avoiding excessive iodine intake. In a well-controlled study the incidence of hyperthyroidism increased by 27% in one year after iodine intake increased from 90 mg per day to the recommended value of 150 mg per day. Subsequently there was a steady decrease in the incidence of the disorder (16).
The problem of IIH demonstrates the need for careful monitoring of the iodine intake of populations after salt iodization has been initiated. This can be done by determining the median urinary iodine level for 40 samples from school- children or preferably from pregnant women. The benefits of correcting iodine deficiency for an entire population far outweigh the risks, which can be minimized by careful monitoring (14).
ICCIDD experience indicates that the nongovernmental organization model can assist a global programme by making it both initially effective and sustainable. We hope that this experience will contribute to the establishment of nongovernmental organizations for the implementation of global programmes in other areas of public health, in collaboration with United Nations agencies. n
Conflicts of interest: none declared.
Elimination des troubles dus à une carence en iode : rôle du Conseil international dans le partenariat mondial
La carence en iode est la plus fréquente des causes évitables de lésions cérébrales. L'OMS estime que 2,2 milliards de personnes sont exposées au risque de carence en iode dans 130 pays. Un programme d'iodation universelle du sel a été créé en 1994 dans le but d'éliminer ce problème à l'horizon 2000. Le présent article fait le point des progrès réalisés, en soulignant en particulier le rôle essentiellement scientifique du Conseil international pour la lutte contre les troubles dus à une carence en iode, organisation non gouvernementale fondée en 1986, et qui consiste maintenant en un réseau multidisciplinaire de 600 spécialistes répartis dans 100 pays.
Eliminación de los trastornos por carencia de yodo: papel del Consejo Internacional en la alianza mundial
La carencia de yodo es la causa prevenible más frecuente de lesiones cerebrales. Según estimaciones de la OMS, aproximadamente 2200 millones de personas estarían expuestas a la carencia de yodo en 130 países. En 1994 se estableció un programa de yodación universal de la sal con la finalidad de resolver este problema antes del año 2000. En este artículo se informa sobre los progresos realizados en esta esfera y se presta especial atención a la función, primordialmente científica, del Consejo Internacional para la Lucha contra los Trastornos por Carencia de Yodo, una organización no gubernamental fundada en 1986. En la actualidad el Consejo constituye una red multidisciplinaria que enlaza a 600 profesionales en 100 países.
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1 Chairman Emeritus, International Council for Control of Iodine Deficiency Disorders, c/o Children's Health Development Foundation, 8th Floor, Samuel Way Building, Women's and Children's Hospital, 72 King William Road, North Adelaide, SA 5006, Australia (email: email@example.com).
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