|The Prevention and Control of Iodine Deficiency Disorders - Nutrition policy discussion paper No. 3 (UNSSCN, 1988, 130 p.)|
|8. ELEMENTS OF NATIONAL IODINE DEFICIENCY DISORDERS CONTROL PROGRAMMES|
A global strategy should be based on national and regional iodization programmes. The particular methods to be adopted to correct iodine deficiency will vary by region and by nation. This may depend on the availability of salt, its pattern of consumption, and the acceptability of iodized salt (see Section 6). Iodized oil, both on a small scale in isolated mountainous regions and on a large scale, has provided a major alternative to iodized salt in many countries such as Zaire where using iodized salt is not feasible.
The gradations of severity of IDD provide the indications for an iodization programme. The classifications based on urinary iodine (see Section 7) may be extended to the following general recommendations.
Mild IDD (Grade I): with urinary iodine (median) more than 50 mcg/g of creatinine1, requires iodized salt (or possibly economic development alone) for the correction and the prevention of goitre.
1See footnote in Section 4.8.
Moderate IDD (Grade 2): with urinary iodine (median) in the range 25-50 mcg/g creatinine, may be prevented by an effective iodized-salt programme; often iodized oil may be necessary in addition, to produce a quantitative correction for the more severely iodine-deficient groups.
Severe IDD (Grade 3): with urinary iodine (median) less than 25 mcg/g of creatinine, requires iodized oil for quantitative correction. Iodized salt might be used as a follow-up measure if economic development permits; but if subsistence agriculture continues, administration of iodized oil needs to be continued.
The availability of suitable technology, while it is the basic requirement, is only one element in an effective iodization programme. The reasons for success and failure in various programmes have been investigated, and political, social and economic factors have all been found to be relevant (Thilly and Hetzel, 1980). A social process is Involved, as demonstrated in Section 6 where individual country programmes are considered.
Figure 7 provides a convenient representation of the relations among these various elements. The steps listed below could be considered as a series of objectives in an iodization programme. A previous form of the model has been published (Thilly and Hetzel, 1980); it has now been updated following further experience in the southeast Asia Region (Hetzel and Dulberg, 1984; Hetzel, 1987).
The model consists of the following six steps.
1. Assessment (collect data, assess situation).
2. Communication (disseminate findings).
3. Planning (develop or update plan of action).
4. Political decision (achieve political support).
6. Monitoring and evaluation.
The process then begins a further cycle with new data, dissemination of the results of the first programme, and development of an improved programme to correct the deficiencies of the first.
It should be emphasized that prevention and eradication of IDD require continual vigilance through regular feedback of epidemiological data Including: estimates of iodine content of salt; iodine content of urine in the vulnerable population (especially school children who are readily accessible through school attendance); goitre prevalence; and levels of T-4 including neonates if possible.
SOCIAL PROCESS MODEL FOR NATIONAL IDD CONTROL