Controlling Iodine Deficiency Disorders in Developing Countries

8/7/2019 Controlling Iodine Deficiency Disorders in Developing Countries

1/49


2/49

CONTROLLINGIODINE DEFICIENCY DISORDERSIN DEVELOPING COUNTRIESDr. David I W Phillips MB BChir PhD MR CP

Oxfam Practical Health Guide No. 5


3/49

Published May 1989Oxfaml989

British Library Cataloguing in Publication DataPhillips, DavidControlling iodine deficiency disorders in developing countries.1. Developing countries. Man. Diseases. Role of iodine

deficiencyI. Title616.3'96ISBN 0-85598-107-5

Published by Oxfam, 274 Banbury Road, Oxford 0X2 7DZ, UKTypeset and Printed by OxfamOX 155/MP/89

This book converted to digital file in 2010


4/49

CO N TEN TS

Introduction 1Chapter 1 The need for Iodine 3Chapter 2 Dietary sources of Iodine 9Chapter 3 Establishing the presence and severity of

Iodine deficiency in a com munity 11Chapter 4 Methods of prevention 21Chapter 5 Carrying out a preventative program me 23Chapter 6 Reporting, monitoring and follow up 27

Appendices1 Suppliers of Iodised oil 292 Adverse effects of Iodised oil 303 Recom mended doses of Iodised oil 314 Further reading and resources 32


5/49


6/49

AKNOWLEDGEMENTSThe advice of Professor Peter Pharoah and Dr John Lazarus is muchappreciated. I am also indebted to the members of the Oxfam HealthUnit for their encouragement and support.


7/49


8/49

INTRODUCTIONFor centuries endemic goitre and cretinism have been recognised ashealth problems particularly in the mountainous parts of the world.The primary cause - iodine deficiency - was identified many yearsago and yet it is estimated that 800 million people in the world todaymay be at risk of developing health problems associated with iodinedeficiency. These conditions, which are now known as "IodineDeficiency Disorders", include not only endemic goi t re andcretinism but also reproductive failure and greater or lesser degreesof mental impairment. They can affect whole communities.Iodization of salt has been used for over 50 years to ensure anadequate supply of iodine in the iodine deficient areas of manycountries. However, in several developing countries programmesbased on the use of iodized salt have failed because of theadministrative difficulties in distributing the salt to remote areaswhere iodine deficiency disorders are most common. In recent years,single doses of a slow-release iodized oil which can be given orallyor by injection have provided an alternative means of prevention.This manual has been written to assist health workers in developingcountries to organise iodine supplementation programmes at thelocal level. Assessing the severity of iodine deficiency is a mostimportant first step and guidance is given on how to conduct surveysof goitre and cretinism. The manual provides up-to-date informationon how to use iodized oil, and ideas for setting up prophylacticprogrammes.


9/49


10/49

CHAPTER 1.

THE NEED FOR IODINEIodine is an essential element which is used by the thyroid gland toproduce the iodine-containing hormones thyroxine (T4) and tri-iodothyronine (T3). These hormones control the body's metabolicrate and are essential for normal growth and development. If thedietary iodine supply is insufficient the thyroid gland cannotfunction properly and the levels of these hormones are reduced. Thiscauses several different health problems.Endemic goitreGoitre or enlargement of the thyroid gland is the commonest andmost obvious effect of iodine deficiency. When more than 10% ofthe adult population in an area have goitres then goitre is said to beendemic. The production of thyroid hormones is controlled by athird hormone called thyroid stimulating hormone (T.S.H.) which isproduced by the pituitary gland (see Figure 1). If there is a dietarydeficiency of iodine the levels of T4 and T3 fall and this causes thepituitary gland to produce more T.S.H. The increase in T.S.H. causesthe thyroid gland to enlarge and, as a result, increase its ability totake up iodine from the bloodstream and produce more thyroidhormones. Goitre is simply the response of the thyroid gland toiodine deficiency.During puberty and pregnancy, the activity of the thyroid gland and,consequently, the body's demands for iodine, are increased. Becauseof this, endemic goitre often appears at puberty and is particularlycommon in wom en of reproductive age.Figure 2 shows how the frequency of goitre varies with age in atypical iodine deficient com munity. It is uncom mon in the early


11/49

Less hormoneproduction

Pituitary gland

Increased thyroidstimulating hormone

Iodine def ic iency

Thyroid Goitre

Figure 1.The mechanism by which a low iodine intake causes endemic goitre

CO1OO-I Soft, diffuse Small nodules Large nodules

N Males

20 30 40 SOAge (years)

Figure 2.The typical pattern of goitre frequency among different ages andsexes in an iodine deficient community. Also shown is the way inwhich the goitre changes with increasing age.


12/49

years of life but increases rapidly in both sexes at around the age ofpuberty. In women it is particularly common during the reproductiveyears, but in men the frequency declines during adult life. Amongthe elderly of both sexes, goitre is seen less often. The type of goitrethat occurs changes throughout life. In children up to the age of ten,goitres tend to be diffuse and soft. Following adolescence there is anincrease in the number of nodules in the thyroid gland. Withincreasing age the bulk of the gland may become occupied bymultiple nodules which can be very large. In the majority ofindividuals, however, goitre regresses with age without noduleformation. It is not known why some individuals and not others formnodules.Usually endemic goitre causes no health problems. If the goitrebecomes very large it may be disfiguring. Occasionally it can causecompression of adjacent s t ructures in the neck such as theoesophagus or trachea leading to difficulties in swallowing orbreathing, but this condition is rare.

Adult hypothyroidismIf the degree of iodine deficiency is severe the thyroid, even byenlarging, may not be able to produce sufficient thyroid horm one. Asa result, signs and symptoms of hypothyroidism may develop.Hypothyroidism results in a general slowing down of the body'sfunctions and is characterised by physical tiredness, reduced mentalability and increased weight. Affected individuals may have a puffyface, coarse skin, and dry hair.Endemic cretinismEndemic cretinism is the most serious result of iodine deficiency. Itis now thought to occur where a child has lacked iodine in fetal orearly neonatal life.The disease is usually found in association with severe endemicgoitre and is recognised by a range of abnormalities. 'Nervous'


13/49

Figure 3Nervous Cretinism. There isobvious mental retardationand the stance is typical withflexed knees and a lumberlordosis.

cretinism (Figure 3) results inirreversible mental retardationtogether with deaf-mutism, andsometimes a squint or otherlocomotor abnormalities (e.g.diplegia). This form is found inseveral South American andSouth Pacific countries.The other major type, known as'Hypothyroid' cretinism, is morefrequent in Central Africa. Themain features are mentalretardation, stunting of growthand signs of hypothyroidism(Figure 4). These, however,represent extremes and often awide variety of abnormalitiesmay be found in affectedcommunities. The mostcommonly seen are mentalretardation, deaf-mutism andgrowth retardation, all of whichmay occur alone or incombination (Figure 5).Controlled trials have beencarried out in both Africa andthe South Pacific conclusivelydemonstrating that the admin-istration of iodine effectivelyeliminates both types ofcretinism.Recent research has suggestedthat even apparently normalindividuals in these areas have


14/49

Figure 4Hypothyroid Cretinism. The features are coarse and puffy, the noseis broad, and there is a prominent abdomen.


15/49

Figure 5The main features of endemic cretinism.mild defects of mental development attributable to iodine deficiency.So, for example, it is known that the administration of iodine togoitrous communities leads to a subsequent improvement of co-ordination, general development and intellectual performance amongchildren. In these circumstances, it is thought that the supplementaryiodine may be acting at two different levels. Correcting iodinedeficiency in the fetal and neonatal period allows for the normaldevelopment of the brain. But iodine could also act in a moreimmediate way to relieve chronic hypothyroidism and so lead to animprovement in mental performance.Other effects of iodine deficiencyIncreased rates of spontaneous abortion, stillbirth and perinatalmortality are also found in iodine deficient communities. It has beenshown that the incidence of these problems can be reduced by iodinesupplementation.In conclusion, it is clear that iodine deficiency results in a widerange of disorders that can affect almost everyone in the communityto a greater or lesser degree. Not only is the quality of life for theindividual impaired, but the effects on the social and economicdevelopm ent of whole areas may be disastrous. A much m oreaggressive approach to iodine supplementation is needed than wasusual in the past.


16/49

CHAPTER 2.DIETARY SOURCES OF IOD INEThe daily requirement of iodine for an adult is approximately 150microgram s per day. Food is the major source of iodine thoughwater may contribu te a little. Most staple foods contain at leastsome iodine but the actual amount depends on how much iodine waspresent in the soil on which the crops were grown. As iodine isconcentrated in animal tissues, meat is a good dietary source ofiodine. The richest natural source, however, is marine fish or otherseafood. Iodine deficiency, therefore, tends to be prevalent where:a) The soil lacks iodine. This is particularly liable to occur in areasof the world affected by past glaciation which removes iodine fromthe soi l . Th is exp lains why end em ic go i t re is com m on inmountainous areas such as the Him alayas or the An des. Iodinedeficient soils are, for other reasons, also found in non-mountainousareas of the world (e.g. large areas of Central Africa).b) The pop ulation in such areas with iodine deficient soils isisolated and underdeveloped, the diet limited to locally grown foodsand lacking meat or other iodine rich foods.c) Marine fish and seafoods are not available.For these reasons, iodine deficiency is most severe in poor, isolated,inland communities in areas with iodine deficient soils.Because of local variations in soil types, the occurrence of iodinedeficiency diseases may be sharply circumscribed, only affecting apart icula r geo grap hical locat ion . The proc ess of econ om icdevelopment often reduces the severity of iodine deficiency as aresult of the diversification of food sources and the consumption ofiodine rich foods (e.g. meat).


17/49

GoitrogensIn discussing dietary sources of iodine, it is necessary to considergoitrogens. These are substances found in food or water that blockthe normal uptake of iodine by the thyroid. A number of goitrogenshave been found in tropical food staples, especially in cassava. Thegoitrogens in cassava are thought to contribute to the goitre problemin Central Africa, though the amount of goitrogen consumeddepends on the method of preparation of the cassava and inparticular the thoroughness of washing prior to cooking. Endemicgoitre has also, at least in part, been attributed to goitrogens in areasof Colombia, Nigeria and Finland. With few exceptions the effect ofgoitrogens can be overcome by adequate iodine supplementation.

10


18/49

CHAPTER 3 .ESTABLISHING THE PRESENCE ANDSEVERITY OF IODINE DEFICIENCY IN ACOMMUNITYThe presence of iodine deficiency in a community is evident to bothdoctor and layman if significant numbers of the affected populationhave visible goitres. Preliminary enquiries in the local comm unitywill help locate the geographical areas which are recognised as beinggoitrous. Alternatively, observation of individuals in places wherelarge numbers of people congregate, for example market places, canbe a useful guide. If endemic goitre is thought to be a problem thenext step is to carry out goitre surveys to quantify the degree ofseverity and delimit the geographical area affected. The goitresurveys together with observations on the frequency of cretinism areused to determine the severity of iodine deficiency.CARRYING OUT A GOITRE SURVEYPlanning and timingBefore any research is carried out, it is important to find out whetherthere is a l ready a nat ion al pro gra m m e in exis tenc e for theeradication of iodine deficiency. In addition there are local formalchannels of approach which differ from country to country. Theappropriate government officials, tribal chiefs, religious leadersand/or village leaders should be consulted. The advice and co-operation of local medical personnel and the staff of health centres isalso essential at different levels, i.e. Regional, District, local.The availability of transport and the time of the rainy season are twofactors to consider when planning a goitre survey. It is also importantto carry out the survey when the population is available and willingto participate. Seasonal activities such as planting or harvesting maytake women away to the fields, or certain national or religious

11


19/49

holidays may prevent the survey taking place at all. Local studiescan usually be carried out easily by primary health care workers inthe area, who can be trained to identify and classify goitre.

Selecting whom and where to surveyTwo types of study can be performed to assess the frequency ofgoitre in an area. The first consists of surveys of school childrenusually of primary school age. This type of study is quick and easyas large numbers of children can be examined in a short space oftime. However, if children are at school, they are likely to be healthy,and many of the severer effects of iodine deficiency, for examplecretinism, will be absent from a school population. Surveys ofschoolchildren in several locations can, though, provide someindication of the geographical distribution and severity of theproblem before embarking on more detailed studies.In the second type of survey an attempt is made to examine everyindividual resident within a defined geographical area, for example,all the people living in a particular village. This is time consumingbut allows for a more accurate assessment of the severity of iodinedeficiency. If the prevalence of visible or palpable goitre (seeChapter 3) is found to be greater than about 10% in schoolchildren,it is recommended that a more detailed community survey shouldthen be carried out.For practical purposes i t is not necessary to measure goitreprevalence to a high degree of precision. A goitre survey must,however, examine a representative sample of the population in thearea. In a rural area, the easiest way to do this is to divide theaffected region into a number of geographical areas of roughly equalpopulation and to select at random one or two villages from eacharea. An attempt should be made to examine every individual inthese villages. As the distribution of goitre tends to be very patchy, itis importan t to ascertain whethe r there are any severely affectedareas in the locality which should be visited separately. Such areas

12


20/49

may be identified from an investigation of locally available recordsand health information, plus informal discussions with local people.Survey techniquesThe normal size of the thyroid varies with both the age and build ofthe individual. It has a firm consistency, is slightly compressible andhas a smooth outline. The lateral lobes can usually be felt lyingbeneath the sternomastoid muscle on both sides of the trachea. Agoitre is present if the lateral lobes of the thyroid have a volumegreater than the terminal phalanx of the thumb of the person beingexamined. It is recommended that two grades of enlargement berecorded:Palpable goitre: an enlarged thyroid that is palpable but not visiblewith the head held in the normal positionVisible goitre: the thyroid enlargement is clearly visible with thehead held in the normal position (see Figure 6).Doubtful cases should be classified as belonging to the lower grade.The presence of nodules should also be recorded. Assessment ofgoitre size is clearly subjective and prone to observer variation. Thiscan be reduced by training which should take place before thesurvey, especially if a number of individuals are to be employed todo the exam inations.Children and adults are examined while standing with their headsheld in the normal position. The neck is first inspected for visiblesigns of thyroid enlargement and then palpated from behind usingthe index and middle fingers of both hands (see Figure 7) . If thesubject bends his neck forwards slightly to relax the neck muscles,palpation is easier and it may be helpful to get the subject to swallowseveral times (a glass of water will help). Free movement of thegland on swallowing distinguishes the goitre from enlargement oflymph nodes.

13


21/49

Figure 6aA large nodular goitre in an elderly woman.

Figure 6bThe goitre in this subject is smaller but still clearly visible.

14


22/49

Figure 7The recommended method of feeling for a goitre.

15


23/49

The surveyIt is important to start with some form of census of the studypopulation. If the study is to be held in a school, the school registercan be used. In a village survey, census data is not likely to beavailable. It can, however, be obtained by a village leader or healthworker who should make a list of all the households and theindividuals resident in each household.Before the survey is carried out forms should be prepared forkeeping a record of the results. An example of such a form is givenin Figure 8, rewriting the data for a household on a single sheet ofpaper. Sim ilar forms can easily be dup licated on cheap paper.Name, age, sex, and geographical location are recorded togetherwith the result of the examination and, where there are severalexaminers, a space for the examiner's initials. Exact age is frequentlydifficult to obtain but for the purposes of the survey broad age-bandsare sufficient, for example, 0-4 years, 5-14 years, 15-44 years, 45years and over.

VILLAGE.LOCALITYDATE OF

HEAD OF

GOITRE

3utooSURVEY. . ?. .*} ? 0. ?k

HOUSEHOLD. '.'?Wj.Q/V!'?*-.

AGE : 15-24 25-34 (^35-44^SEX : fGOITRE

1. NAME.

rT) F

SURVEY

45 or

1 'N: NIL ^PALPABLE) VISIBL E

...^k,w^pAGE : 0-4 5-9 10-14 15-24SEX : MGOITRE :

2. NAME.

NIL PALPABLE (VISIB

- S i ^ -

(fs-34)

11 / OIL

NO. IN HOUSEHOLD. . 5. ...

over


24/49

It is also important to give advance warning to the communitybefore the day of the survey. This could be done via the villageleader/health worker, or an announcement could be read out in achurch or any other place where people congregate. When thesurvey team enters the village a simple explanation should be givenin the local language. To carry out the survey, it is helpful to set up a'line of flow' with a number of desks at which different tasks areperformed. Each household is called forward in turn. At the firstdesk the basic demographic details are recorded. At the secondstation the thyroids are examined and signs of cretinism (deaf-mutism and mental retardation) are also noted. If treatment is to begiven at the same time (see Chapter 5), this can be carried out at athird station. With proper organisation it is possible to examine 100-200 people per hour. In order to make the sample studied asrepresentative of the total population as possible, an attempt shouldbe made to locate families or individuals who have not attended.Houses or compounds may have to be visited by the survey team, asin some parts of the world handicapped or abnormal individuals maybe concealed by their families.

Figure 9Carrying out a goitre survey in a village in the Northern K ivu area ofZaire.

17


25/49

Analysis and presentation of resultsThe goitre prevalence should be calculated for each sex and agegroup. The prevalence of 'overall' goitre (palpable and visiblegoitre) and the prevalence of visible goitre should be worked outseparately (an example is shown in Table 1).Observations to supplement endemic goitre surveysCretinism, deaf-mutism and mental deficiency are associated withsevere endemic goitre. An effort should be made, therefore, todiscover the existence of such cases in endemic areas and if possibleto verify the diagnosis by examination of each reported case. Themain features of cretinism are deaf-mutism and mental retardation. Ifa child is said to be deaf, simple clinical examination can confirmthis and examination of the ear-drums should be carried out toexclude otitis media and/or perforation. Cretins frequently haveassociated neurological defects such as a squint, abnormalities ofgait (widestepping gait) and in severe cases, a spastic diplegia. If thecretinism is of the 'hypothyroid' variety the predominant features aremental retardation, growth retardation, coarsening of the features, arough dry skin and a protruberant abdomen.Interpretation of the resultsEndemic goitre has been defined as a prevalence of palpable goitrein 10% or more of the adults in a community. As the iodinedeficiency gets more severe, goitre prevalence rises. Males areaffected as often as females and goitres are found in very youngchildren and sometimes even in newly born babies. The results ofthe goitre survey and the prevalence of cretinism should becompared with the classification of severity in Table 2. In assessingthe severity of iodine deficiency the presence of cretinism is veryimportant and if cretins are found, this is an absolute indication forinitiating an iodization programme. In lesser degrees of iodinedeficiency the decision as to whether to embark on a programme isless easy and has to be weighed against other health priorities in thecommunity.

18


26/49

TABLE 1SAM PLE TABULATION OF GOITRE SURVEYDATAVillage RukingoArea BwesoDate January 1986

Age

Males:0 -45-14

15-4445+

Females:0 -45-14

15-4445+

TotalPopulation

29274510

28384014

Number withpalpable goitre

132037

5

20303510

%(45)(74)(82)(50)

(71)(79)(87)(71)

Number withpalpable andvisible goitre

29

161

89

302

%( 7)(33)(35)(10)

(28)(24)(75)(14)

19


27/49

TABLE 2ASSESSING THE NEED FOR AN IODIZATIONPROGRAMME

Overall GoitrePrevalence

Above 70-80%

30-70%

Less than 30%

Prevalence ofcretinism

Population athigh risk fromendemic cretinism.

Population notat risk fromcretinism.Hypothyroidismmay occur.

Observations

Iodizationprogrammeneeded.

Cost of iodizationprogramme shouldbe balanced againstother health needsin the area.

Goitre may be seenbut iodization unlikelyto be a healthpriority

20


28/49

CHAPTER 4.METHODS OF PREVENTIONThe aim of preventative measures is to provide the daily iodinerequirement of 150 microgram s per day. Various methods have beenused to achieve this and the choice to some extent depends on localcircumstances.Iodine supplem entation of foodIodization of salt has been the mainstay of preventative programmesin developed countries. The iodization is normally organised on anational or regional basis. The amount of iodine supplement iscalculated on the basis of the amount of salt consumed and thequantity of iodine required. In many developing countries, however,salt iodization programmes have been hampered by administrativedifficulties in manufacturing the salt and in ensuring that it replaceslocally produced salt, or in distributing it to remote areas - wheregoitre and cretinism tend to be most common. Another disadvantageof using iodized salt in tropical countries is the loss of potency inhumid conditions. Even in stitched plastic bags, half the addediodine is norm ally lost after nine m on ths ' storage, but in veryadverse conditions up to 90% of the iodine could be lost during thistime.Iodized oilIn areas where salt iodization is not feasible, single doses of iodizedoil have been used to provide a long lasting source of iodine. Iodizedoil is a vegetable oil to which iodine has been added. Currentsupplies contain 475mg iodine per ml (37% iodine by weight). A listof suppliers is given in Appendix 1. The oil can either be given byinjection or orally. Most studies with injected oil have showneffective supplementation for three to four years following a 2ml

21


29/49

dose. Iodized oil given orally appears to be effective for mediumterm prophylaxis, a 2ml dose being sufficient for up to two years.OTHER METHODSIodide tablets, Lugol's iodineThe distribution of iodide tablets on a weekly basis has been triedbut has not generally proved successful largely due to organisationaldifficult ies. The use of large single doses of iodide is alsoineffective.

L-thyroxineThyroxine tablets are widely used in developed countries to treatnon-toxic goitres. However, it is much more expensive but no betterthan iodine supplementation and i t is also more complex toadminister.Partial thyroidectomySurgery should only be considered after iodine supplementation hasfailed to reduce goitre size, and then only if compression of adjacentstructures in the neck is a problem. Partial thyroidectomy is adifficult and dangerous operation to perform if facilities are limited.If the patient returns to the iodine deficient area there is also the riskof recurrence or of hypothyroidism.

22


30/49

CHAPTER 5.CARRYING OUT A PREVENTATIVEPROGRAMMEChoice of methodThis will depend on local circumstances, the severity of the problemand the means available to reach individuals at risk. The sale ofiodized salt may be feasible, but if the marketing infrastructure ispoor and salt traditionally obtained from a variety of sources, iodizedoil should be be used. Iodized oil is also more practicable where theaffected population lives in small, scattered rural communities. Thechoice between giving iodized oil orally or intramuscularly will beinfluenced by the availability of trained workers capable of givingsafe injections, cost and acceptability in the local community.The use of injections may also risk spreading AIDS infection andhepatitis B, particularly if needles are re-used and not properlysterilised (Table 3). In a recent African program me using orallygiven oil, it was found that large communities could be treatedrapidly with virtually untrained assistants. However, treatment withoral oil must be repeated every two years. In areas where the iodinedeficiency is marginal, treatment could be restricted to certain agegroups. Giving iodized oil only to wom en of childbearing age andschoolchildren may be more cost effective in these circumstances.Current dosage recomm endations are given in Appendix 3 .Funding the campaignThe major cost of an iodization programme is the iodized oil. Thecurrent (1989) price from manufacturers varies between 2 and 5for 10ml, and therefore any large scale eradication programme willbe relatively expen sive. However, it is expected that low costpreparations of iodized oil suitable for oral use will becomeavailable within the next few years, as research and development is

23


31/49

TABLE 3THE CHOICE BETWEEN ORAL ANDINTRAMUSCULAR IODIZED OIL

ORAL OIL

Prophylaxis for two years.

Can be given by untrainedassistants.

Easy and quick to give.Safe under all conditions.

Cheaper.

INJECTED OIL

Prophylaxis for three to fouryears.

Needs trained personnel.

Injections take longer to give.Risk of causing injectionabscess or spreading AIDS orhepatitis infection through poorsterilisation techniques .

Additional cost of syringes andneedles, sterilisation equipmentand consumables, i.e. cottonwool, spirit etc.

24


32/49

currently in progress. Funding from charities and aid agencies willprobably be necessary if a large scale project is contem plated.Promoting the campaignIt is important to stimulate community awareness of the problem andthe proposed prophylactic measures early in the programme.Clearly, the campaign will not work if people are not fully aware ofthe reasons for it, the way it will operate and exactly what is going tohappen. It is wise, at the start, to approach government officials andlocal leaders to get their backing and advice, particularly on anyaspects of the campaign that may offend local sensibil i t ies.Discussions with the staff of local health centres and hospitals couldbe a starting point, followed by talks with village health workers andcommunity leaders in the area, giving a full explanation of theprogram me. The comm unity at large could be made aware of theprogramme through announcements in churches and mosques, theuse of posters and possibly by using local media includingnewspapers and radio. The explanation of the program me needs tobe put in simple terms easily understood by poorly literate peopleand the benefits of the treatment should be stressed.Carrying out the programm eThe objective of the programme is to administer iodized oil toeveryone in the affected area, even if they do not have a goitre. If thevillages have not previously been visited to ascertain the prevalenceof goitre and cretinism, this data should also be collected during theinitial treatment phase. It is also useful to have census data on thepeople in each village which can be obtained as described in thesection on goitre surveys. As the programme is being carried out, thevillage headman should be present to identify which families belongto the village, to make sure that individuals receive only one dose.Efforts should be made to obtain a good take-up rate for thetreatment. The objective should be to treat at least 80% of thepopulation. Side effects are uncommon (Appendix 2) - the most

25


33/49

commonly observed is transient pain and swelling of the salivaryglands.There are a number of ways in which a programme can be carriedout:a) Special teams can be formed consisting of two or three auxiliarymedical workers who have undergone a short training course. Eachteam should be able to treat several hundred individuals per day.b) The preventative programme can be integrated with a vaccinationprogramme. Mothers and children should be encouraged to attendand the treatment with iodized oil offered together with theimmunizations.c) A prophylactic programme concerned with eradicating iodinedeficiency disorders can be used as an opportunity to establish aprimary health care programme in a remote area which previouslyhas had little or no contact with W estern medicine.

26


34/49

CHAPTER 6.REPORTING, MO NITORING ANDFOLLOW-UPIt is important to report back to the government health department ornat ional organisat ion co-ordinat ing the prevent ion of iodinedeficiency both the survey findings and the number of treatmentprogrammes that have been completed.Monitoring helps to ensure that the work is being carried outefficiently and to identify problem s. Monitoring should be carriedout at regular intervals during a treatment programme and a numberof questions need to be asked.

Are the survey techniques (e.g. goitre grading) being carriedout correctly?Is the coverage adequate?Are the forms of treatment given acceptable?Are there any other problems with the program me?

Follow-up should be carried out at approximately two-yearlyintervals on samples of the target population. The prevalence ofgoitre and cretinism should be assessed. Goitre prevalence willdecline in the months following supplementation, though this has notbeen observed in every endemic area. The decline will be mostmarked among the young and those with soft, diffusely enlargedthyroid glands. Subjects with hard, nodular glands will rarely noticeany change. In addition, no new cretins should have been born sincethe initial visit (except to mothers already pregnant at that time).

27


35/49


36/49

APPENDIX 1SUPPLIERS OF IODIZED OILFrance Trade nam e: Lipiodol Ultrafluide

Andre Guerbert Laboratories24 rue Jean-Chaptal93609 Aulnay-Sous-BoisCedex PARISFRANCE

United Kingdom Trade nam e: Lipiodol Ultra-fluidMay and BakerRainham Road SouthDagenhamLONDON RM10 7XS

USA Trade nam e: EthiodolSavage Laboratories1000 Main StreetMissouri CityTx 77459USA

China Fourth Pharmaceutical Factory24 Wen-Ming RoadWuchangWuhanPRC

29


37/49

APPENDIX 2ADVERSE EFFECTS OF IODIZED OILHyperthyroidism may occur following iodized oil administrationparticularly in individuals aged over 40, or those with large nodulargoitre. For this reason the dose of oil should be reduced in thisgroup. Hyperthyroidism usually presents as weight loss, tremor orsweating in association w ith fast heart rate.

Transient sialadenitis (pain or swelling of the salivary glands) mayoccur particularly after giving iodized oil orally.

Occasionally allergic reactions are seen (e.g. a rash).

There is no evidence of an adverse effect on fetal survival or theoccurrence of neonatal goitre or hypothyroidism following its use inpregnancy.

30


38/49

APPENDIX 3RECOM M ENDED DOSES OF IODIZED OIL

INJECTED OILAge Dose mlUnder 1 year 0.51-5 years 1.06-45 years 2.0

N.B. This dose should be reduced to 0.2ml for all persons withnodular goitre or presenting single thyroid nodules.

ORAL OILThere is not enough information to make precise recommendationsabout dosage.Current studies suggest that lml would give coverage for one yearand 2ml for two years.

31


39/49

APPENDIX 4FURTHER READING AND RESOURCESThe International Council for Control of Iodine DeficiencyDisorders publishes a quarterly newsletter. It is available, free ofcharge, by writing to Dr J.T.Dunn, Box 511, University of VirginiaMedical Centre, Charlottesville, VA 22908, USA.Teaching Aids at Low Cost (TALC) produces a set of slides andcommentary for teaching public health workers and nutritionists inareas where iodine deficiency is a problem. It is available fromTALC, PO Box 49 , St Albans, Herts, AL1 4AX , UK.Towards the Eradication of Endemic Goitre, Cretinism and IodineDeficiency is avai lable from the P an Am e r i c an H e a l thOrganisation (PAHO Publication No.502, edited by J. T. Dunn etal) and provides information on iodine deficiency in Africa, Asia andLatin America. (PAHO, 525 23rd St., N.W. Washington D.C. 20037,USA).Iodine-Deficiency Disorders in South-East Asia has been producedby the W HO regional office for South-East Asia in New Delhi(SEARO Regional Health Paper No. 10). It provides a review of IDDand data on programmes in Asia. Available from W.H.O. RegionalOffice for South East Asia, World Health House, New Delhi 110002, India.For an up-to-date and more technical review see "Endemic goitreand iodine deficiency disorders - aetiology, epidemiology andtreatment" by C. J. Eastman and D.I.W. Phillips (Baillieres ClinicalEndocrinology and Metabolism Vol.2, No.3 August 1988, pp.719-736, edited by R. Hall and J.H. Lazarus).

32


40/49


41/49

OXFAM PUBLICATIONS ON HEALTHSELECTIVE FEEDING PROGRAMMESPrice 2.95ISBN 0 85598 097 4Originally produced to accompany the Oxfam Feeding Kit at a timeof the large- scale famine in Ethiopia in the 70s, this book has beenexpanded into a comprehensive manual for use in treating differentdegrees of malnutrition in emergency situations. The first part of thebook describes the assessment and monitoring of the nutritionalneeds of the population at risk; Part Two gives detailed directionsfor the setting up and administration of selective and therapeuticfeeding pro gra m m es. Th ere are several useful append ices -chec klists, tables, recipes, etc. This book prov ides all the basic,essential information for those working in the fields of health andnutrition faced with emergency relief situations.Oxfam Practical Health Guide No. 1

REFUGEE HEALTH CAR EPrice f 1.50ISBN 0 85598 098 2This thoroughly practical guide is intended for health workers indisaster relief and refugee emergency pro gra m m es. It outlinespolicy guidelines recommended for the three main stages ofprogram me developm ent - emergency a ssessmen t, init ial reliefprovision and consolidation. A series of technical appendices focuson m ore specific aspects of the response to an emergency. Theappendices provide more detailed a"dvice on nutritional surveys,feeding programmes, water and sanitation provision, immunisationand tuberculosis control, health worker training and drawing up ahealth program me and action plan.Oxfam Practical Health Guide No. 2

34


42/49

IMPLEMEN TING M ULTIPLE DRUG THERAPY FORLEPROSYPrice 2.95ISBN 0 85598 074 5The system of multiple drug therapy for leprosy recommended bythe World Health Organisation in 1982 is an extrem ely effectivetreatment w hich, if widely introduced and effectively operated, couldresult in a dramatic reduction of the incidence and severity ofleprosy throughout the world. This book, written in the form ofextended answers to a series of questions, deals with a variety ofaspects of the care and management of patients undergoing multipledrug therapy. It is aimed essentially at those in senior positionsconcerned with teaching health workers, programme planning andimplementation of leprosy control programmes.Oxfam Practical Health Guide No. 3

TUBERCULOSIS CONTROL PROGRAMMES INDEVELOPING COUNTRIES Price 2.95ISBN 0 85598 098 2Tu berc ulos is is l ikely to rema in a major h eal th prob lem indeveloping countries as long as communities face poor housing,overcrow ding and poor nutrition. Many coun tries have nationaltuberculosis control programmes, but these are seldom as effectiveas they could be because of difficulties in implementation at villagelevel. This book combines the most recent developm ents in thescientific understanding of tuberculosis with the realities of workingat the level of a primary health centre and suggests ways ofimproving the efficiency of tuberculosis control programmes by anincreased understanding of the importance of the sputum-positivepatient as the source of transmission and therefore the target ofcon trol. It looks at the prob lem s of diagnosing and poo r drugcompliance, and emphasises the importance of monitoring andevaluation of tuberculosis prog ram m es. It will be a valuable

35


43/49

practical handbook for those working in health care projects indeveloping countries.Oxfam Practical Health Guide No. 4

CITIES OF HUNGERUrban Malnutrition in Developing CountriesISBN 0 85598 085 0 Hardback 19.95ISBN 0 85598 084 2 Paperback 4.95By the end of the century, half the world's population will live incities, so the need to improve the conditions of life of the urban pooris becom ing increasingly urgent. A specific problem for poor city-dwellers, which to date has been under-researched, is that ofproviding sufficient food for them selves and their children. Cities ofHunger, an important contribution to nutrition studies, focuses on thecauses of urban malnutrition and adopts an innovative way ofanalysing these in terms of the social level - individual, family,community, national/international - at which they operate.The second part of the book provides a detailed examination of threeprojects in contrasting urban settings and describes how their waysof working evolved dynam ically. It relates these changes and thesuccesses and failures of the projects to the analysis developed in thefirst part of the book.Cities of Hunger will be of interest both to those working in the fieldof health and nutrition in particular, and those with a more generalinterest in development.

36


44/49

READER EVALUATIONOxfam is always seeking to improve the quality of its publications.To help us gauge reader opinion, we invite comm ents from you. Thispage is for your criticisms and suggestions. Please send to: OxfamPublications, 274 Banbury R oad, Oxford, 0 X 2 7DZ .Controlling Iodine Deficiency Disorders in Developing CountriesName:Address:Comments:


45/49


46/49

notes


47/49

notes


48/49

notes


49/49

notes

Controlling Iodine Deficiency Disorders in Developing Countries

Documents

Transcript of Controlling Iodine Deficiency Disorders in Developing Countries