ECONOMIC EVALUATION OF WATER IODIZATION PROGRAM IN THAILAND

ECONOMIC EVALUATION OF WATER IODIZATION PROGRAM IN THAILAND CS Pndv 1, K Annd 1, Sngsom Sinwt 2 nd FU Ahmed 1 1 IDD Study Group, All Indi Institute of Medicl Sciences, New Delhi, Indi; 2 Division of Nutrition, Ministry of Public Helth, Nonthburi, Thilnd Abstrct. In Thilnd, iodine deficiency disorders (IDD) re endemic in 57 out of 75 provinces with n estimted 15 million people t risk of IDD. A three pronged control progrm with iodized slt, iodized wter nd iodized oil cpsules is being implemented. The wter iodiztion progrm is both school bsed nd household bsed. In the household, the residents re given iodine solution, two drops of which is to be dded to 10 l of drinking wter. In the schools, in ddition to this method, n iodintor is used. This releses fixed mount of iodine into the drinking wter. This study exmines the cost of the wter iodiztion progrm in Thilnd for the yer 1996 in terms of cost per beneficiry, cost per µg iodine consumed dily nd cost per goiter person yers verted. We used discount rte of 5%. Field visit nd interviews of helth personnel from Ministry to villge level were conducted to gther primry dt. Review of existing ppers nd reports of the Deprtment of Helth, Government of Thilnd ws done for secondry dt. The costs included the cpitl cost of equipments, initil trining nd the recurrent costs of potssium iodte, proportionl slries of personnel involved, monitoring nd communiction ctivities. The cost per beneficiry of school bsed iodintor method (US$ 0.72) nd school bsed drop method (US$ 0.64) were similr nd much higher thn the household bsed pproch (US$ 0.12). The cost per µg of iodine consumed dily ws ten times higher in the school bsed pproch (US$ 0.01) compred to the household pproch (US$ 0.001). The cost per goiter cse verted for the whole strtegy of wter iodiztion ws US$ 194.50. Wter iodiztion ppers to be low cost intervention. However, the need for behviorl modifiction rises the issue of long term sustinbility. INTRODUCTION Iodine deficiency disorders (IDD) re mjor public helth problem in Thilnd. The initil reports on the goiter belt in northern Thilnd by Pringpungko in 1953 nd Rmlingswmi in 1955 were confirmed by Klerks in 1957 (Ministry of Public Helth, 1992). With the ssistnce from World Helth Orgniztion (WHO) nd UNICEF, the Ministry of Public Helth begn pilot slt iodiztion project in Pre Province in 1965. This project ws successful in decresing the prevlence of goiter. The progrm ws lter expnded to the rest of the country in phsed mnner (Ministry of Public Helth, 1992). In the resurvey conducted in 1988, it ws noted tht the sitution hd worsened. In eight to fourteen provinces of northern Thilnd endemic goiter ws widely prevlent. This necessitted urgent remedil mesures. (Ministry of Public Helth, 1992). Therefore in My 1989, The Ntionl IDD Control Project ws strted. It ws felt tht the current sitution clled for use of ll the vilble Correspondence: Dr Chndrknt S Pndv, Center for Community Medicine AIIMS, New Delhi - 110029, Indi. control mesures which included iodized slt, iodized wter nd iodized oil cpsules (Ministry of Public Helth, 1992). Surveys till 1993 reveled tht 57 out of the 75 provinces covering ll regions hve IDD s public helth problem. The overll prevlence rte of goiter ws 9.8% with n estimted popultion of 15 million people belonging to the, risk group (Ministry of Public Helth 1994, 1996). It ws decided tht slt iodiztion would be the principl mesure to combt IDD. Socil mrketing of dequtely iodized slt ws supported by pproprite legisltion nd its enforcement. Other supplementry mesures such s iodized drinking wter, fish suce were lso encourged wherever nd whenever possible. Iodized oil ws reserved for ppliction only in some specific high endemic res nd high-risk trget groups. To mke this progrm effective, communiction ctivities nd inter-sectorl co-ordintion were lso strengthened (Ministry of Public Helth, 1994). Currently in Thilnd, the mesures for IDD prevention nd control re the following (Pisolbutr, 1994): 1. Iodized slt : All districts of ll provinces. 762

ECONOMIC EVALUATION OF WATER IODIZATION IN THAILAND 2. Iodized wter: All primry schools nd households in 39 project provinces, s well s some provinces in southern Thilnd re covered. An estimted 50% of the popultion of Thilnd is covered by this strtegy. The iodiztion of wter is crried out t school nd household. Two methods re used for iodiztion: drop method nd iodintor method. The schools use either drop method or iodintor method. The Households use only Drop method. 3. Iodized oil cpsules re dministered to pregnnt women, women in the childbering ge, school children. The cpsule progrm is being crried out only in districts with goiter prevlence bove 20%. The cpsule strtegy is to discontinued when the prevlence of these districts fll below 20%. The three pronged cmpign is short term mesure. In the ner future, only single strtegy would be dopted for the country. The choice would depend upon the effectiveness of the strtegy including cceptbility nd complince, cost of the strtegy nd sustinbility of the strtegy. With this objective in mind, n economic nlysis of wter iodiztion progrm in Thilnd ws performed. The outcome mesures were: i) Cost per beneficiry ii) Cost per µg iodine consumed dily iii) Cost per goiter person yers verted. MATERIALS AND METHODS This study ws done t the request of Interntionl Council for Control of Iodine Deficiency Disorders. The Government of Thilnd, especilly the Division of Nutrition in the Ministry of Public Helth, co-operted fully in providing ll the relevnt detils nd lso rrnging field visits. For this study, societl viewpoint ws dopted. A discount rte of 5% ws used nd ll the costs were clculted with 1996 s the reference yer. The informtion for the study ws collected by (i) interviews of concerned people, (ii) field visits nd (iii) review of published literture of existing ppers nd reports. Interviews were held with the Director of Public Helth; Director nd Stff of Division of Nutrition, Provincil, District nd Villge Helth Officils; school principl, techers nd students; community leders, villge helth volunteers nd community members. Field visits were mde to Chom Thong, Chiprkrn nd Smoeng districts of Ching Mi Province nd Lmpng Province. Interviews were conducted with the help of interpreters. This field visit ws crried out in September, 1996. During the field visit, informtion on time devoted for IDD ctivities ws collected from the service providers s well s the dynmics of use t household nd school level. The studies conducted by the Ministry of Public Helth on wter iodiztion were lso reviewed. Method of iodiztion of wter Two methods of wter iodiztion re followed in Thilnd; iodintor method nd drop method (Ministry of Helth, 1994; Pisolybutr, 1994). The schools use either drop method or iodintor method. At the household level, only the Drop method is used. Drop method The Public Helth Deprtment gives pckets of potssium iodte to the helth workers nd techers. Ech pcket contins 24 g of KIO 3. The techers re trined to prepre KIO 3 solution by dding 725 ml of wter (For mesuring 725 ml, Mekong whisky bottle which is redily vilble is used). This solution is then poured into 24 plstic bottles of 30 ml ech (single bottle kit). This plstic bottle is then given to the student leder who hs the duty of dding the KIO 3 solution to the drinking wter of the school on dily bsis. Two drops of this solution is dded to 10 l of drinking wter. This provides 200 µg iodine per liter of wter. In the school, glss of 200 ml is used for drinking iodized wter. Every dy, ech child hs to drink minimum of two glsses. This ctivity is supervised by the school hed boy nd designted techer. For child who drinks two glsses of wter (400 ml), this method would ensure minimum intke of 80 µg of iodine per dy. Household The helth workers prepre the solution s described bove nd give it to the helth volunteers. The volunteers collect this nd supply the single bottle kit to the households. They lso explin to the community bout its use. At household level, the fmily designtes member, usully young dult who puts two drops of solution for every 10 l of wter on dily bsis. This provides 200 µg of iodine per liter of wter. 763

Iodintor method Iodintor is device for slow relese of potssium iodte (KIO 3) into wter supply for drinking. Iodintor is fitted into the outlet of the wter reservoir. It contins smll jr which holds the concentrted potssium iodte solution. The mount of iodine relesed depends upon the pressure of the uniodized wter flling upon vlve. The min wter flows t rte of 5 liters/minute nd the KIO 3 t 1 drop/minute. The flling wter nd concentrted iodine solution re then collected together in nother tnk which is used for drinking purposes. The iodinted wter then contins iodine in the concentrtion of 100 to 400 µg/l. Monitoring The monitoring of iodinted slt nd iodized wter is done with the help of kit developed by Suwnik (Ministry of Public Helth, 1992). Monitoring is crried out by the helth workers t regulr intervls of three months on rndom smpling bsis. There is currently no system of record keeping for the monitoring. Therefore, there is no mechnism in plce for giving feedbck to the system. An pproprite Mngement Informtion System (MIS) is being developed. Costing methodology All the costs were mesured initilly in Bhts. The finl results were then converted to US$ using the exchnge rte of 1 US$ = 25 Bht. The costs were divided into cpitl costs nd recurrent costs. Cpitl costs: Cpitl cost includes cost of items which hve life of more thn one yer. Tht is, items which re needed t the onset of progrm, like equipments, etc but whose cost is pplicble for period exceeding one yer. The ctegories included under cpitl costs re shown in Tble 1. It cn be seen tht the initil trining is lso cpitl cost s it is one time ctivity but its use lsts for period of more thn one yer. The cost of instlltion of wter supply system like filtrtion tnks etc hve not been included in the cost s these would hve to be provided irrespective of wter iodiztion progrm. Bsed on the life of ech equipment nd discount rte, equivlent nnul cost (EAC) ws clculted. Recurrent costs: This includes the cost of items which re incurred on n nnul bsis, eg potssium iodte, slry of personnel etc. The complete list is given in Tble 2. Totl nnul cost The totl nnul cost incurred on strtegy is the sum of equivlent nnul cost nd recurrent cost clculted for ech yer. Description of unit costs The verge popultion of villge in Thilnd is estimted to be round 1,000 (Ministry of Public Helth, 1996). All the clcultions hve been estimted for such villge. Cost per beneficiry For the household strtegy, s the beneficiries will be the whole villge, the cost per beneficiry is the totl cost of the strtegy divided by 1,000. Tble 1 Estimted cpitl cost (in Bhts) of different strtegies for wter iodiztion in Thilnd for the yer 1996. Item School bsed using School bsed using Household-bsed with iodintor method drop method drop method Totl Equivlent Totl Equivlent Totl Equivlent cost nnul Cost cost nnul cost cost nnul cost Iodintor, ccessories 8,000 1,036 NA NA NA NA nd instlltion cost Mnuls/books 1,500 194 1,500 194 - - Trining 800 104 800 104 300 41.5 Totl 10,300 1,334 2,300 298 300 41.5 NA : Not pplicble. 764

ECONOMIC EVALUATION OF WATER IODIZATION IN THAILAND For the school bsed strtegy, the cost per beneficiry is the totl cost divided by the number of school children. From the vilble sttistics of Thilnd, it cn be inferred tht the number of beneficiry school children in the ge group of 6 to 14 yers in villge of 1,000 will be round 200. For the clcultion, the student enrollment nd ttendnce hs been tken s 100%. On the bsis of interviews of school stff, the totl period of functionl schooldys in yer hs been estimted s 200 dys. Cost per µg iodine consumed dily For both the strtegies, especilly for household strtegy, the complince of villgers in dding iodine is n importnt determinnt of effectiveness of the strtegy. This issue is not ddressed in the bove indictor, s ultimtely the impct depends on the ctul iodine intke of the popultion. A new costing unit (cost per µg iodine consumed dily or mg iodine consumed per yer) ws used in this study. The expected dily dose of iodine (300 µg for person consuming 1.5 l of wter iodine concentrtion of 200 µg/l) multiplied by complince would give the ctul dose of iodine consumed. The estimtes of complince were bsed on study conducted by the Ministry of Public Helth (1993). This cme to 187.5 µg per dy. The cost per µg iodine consumed dily ws clculted by dividing the totl dily cost of household wter iodiztion by dily dose of iodine consumed. Cost per goiter person yer verted in school children For this estimtion, the informtion on the decline in the goiter prevlence fter introduction of wter iodiztion progrm ws required. However in Thilnd, s ll the three strtegies were introduced simultneously in n re, it ws difficult to estimte the impct of wter iodiztion progrm lone on IDD indictors. Though some dt on effectiveness were vilble from different pilot studies of wter iodiztion done t different times, the results were not generlizble to the ctul implementtion of the progrm. Bsed on dt from selected provinces in Thilnd, first, we clculted the rte of decline in goiter prevlence due to combined wter nd slt iodiztion strtegy. We then ssumed tht both the strtegies re eqully effective nd if implemented optimlly, their individul impct would be proportionl to their utiliztion. RESULTS The costs of three different strtegies of wter iodiztion for control of IDD in Thilnd ws estimted. These costs hve been estimted for villge of 1,000 popultion hving one school with n estimted popultion of 200 school children in the ge group 6-14 yers with 100% school ttendnce. The cpitl costs of different strtegies of wter iodiztion is shown in Tble 1. The equivlent nnul cost (EAC) ws mximum for school bsed wter iodiztion method (Bhts 1,334, US$ 53.4) followed by school bsed drop method (Bhts 298, US$ 12) nd household bsed drop method (Bhts 41.5, US$ 1.7). The cost of school bsed iodintor method ws high becuse of the high cost of iodintor nd its instlltion. The nnul recurrent costs of the three strtegies re shown in Tble 2. The recurrent cost for household bsed drop method ws mximum (Bht 2,930, US$ 117.2) compred to school bsed drop method (Bht 2,885, US$ 115.4) nd school bsed iodintor method (Bht 2,241, US$ 89.6). The cost in the household method ws high becuse it is for 1,000 popultion compred to school bsed strtegy which is for 200 school children only. It should lso be noted tht more thn 50% of the recurrent cost ws on Informtion, Eduction nd Communiction. This ppers to be logicl s ll the three strtegies im t behviorl chnge in the community. The totl cost (equivlent nnul cost nd recurrent cost) of the three strtegies is shown in Tble 3. The school bsed iodintor method hd the highest cost (Bht 3,575, US$ 143) wheres the household bsed strtegy hd the lest cost (Bht 2,971.50, US$ 119). The cost per beneficiry of the three strtegies is shown in Tble 4. The cost per beneficiry ws the lest in the household bsed pproch s the totl cost ws spred over lrger popultion. The cost of both the school bsed pproches were roughly the sme nd ws five to six times the unit cost of household bsed pproch. For the clcultion of cost per µg iodine consumed dily, it is necessry to first estimte the iodine consumption through the iodized drinking wter. For iodintor strtegy, 100% complince ws ssumed s it is now prt of wter supply. Thus, ssuming consumption of hlf liter of 765

Tble 2 Recurrent nnul cost (in Bhts) of different strtegies of wter iodiztion in Thilnd for villge with one school for popultion of 1,000 for the yer 1996. Item School bsed School bsed Household bsed iodintor method drop method drop method Potssium iodte 10 10 1,250 Personnel 171 1,215 120 District officer 15 15 NA School principl 18 180 NA School techer 12 900 NA School worker 6 NA NA Helth worker 120 120 120 Helth volunteer NA NA Not included Refresher trining 45 45 45 IEC 1,500 1,500 1,500 Monitoring 15 15 15 Mintennce 500 100 0 Totl 2,241 2,885 2,930 NA : Not pplicble. Tble 3 Totl cost (in Bht) of different strtegies of wter iodiztion in Thilnd for the yer 1996. Method (EAC) cpitl costs Recurrent nnul cost Totl School bsed iodintor 1,334.00 2,241.00 3,575.00 School bsed drop 298.00 2,885.00 3,183.00 Household bsed drop 41.50 2,930.00 2,971.50 Tble 4 Comprison of cost per beneficiry of different strtegies of wter iodiztion in Thilnd for the yer 1996. Strtegy Totl cost No. of Cost per beneficiries beneficiry School bsed iodintor method 3,575.00 (US$ 143) 200 17.90 (US$ 0.72) School bsed drop method 3,183.00 (US$ 127) 200 15.90 (US$ 0.64) Household drop method 2,971.00 (US$ 119) 1,000 3.00 (US$ 0.12) 1 US$ = 25 Bhts. wter with the iodine concentrtion of 200 µg/l for 200 dys in yer gve n dily consumption of 54.8 µg of iodine. For the school bsed drop method, the complince rte of 80% ws ssumed (includes techer/student forgetting to dd iodine nd children not drinking the wter). This cme to 43.8 µg (54.8 * 0.8) of iodine per dy. For household strtegy, it ws ssumed tht, 40% of the popultion did not use iodized wter, 12% use on some dys (ssumed to be 50% of the time) nd 48% use every dy. This gve per cpit dily consumption of 108 µg of iodine. The cost per µg of iodine consumed dily for the three strtegies is shown in Tble 5. 766

ECONOMIC EVALUATION OF WATER IODIZATION IN THAILAND Tble 5 Cost per µg of iodine consumed dily for the three strtegies for the yer 1996. Strtegy Totl cost µg of iodine Cost (Bht) per µg of (Bhts) consumed dily iodine consumed dily School bsed iodintor 3,575 (US$ 143) 54.8 0.33 (US$ 0.01) School bsed drop method 3,183 (US$ 127) 43.8 0.36 (US$ 0.01) Household 2,971 (US$ 119) 108.0 0.028 (US$ 0.001) 1 US$ = 25 Bths. Cost per goiter person yer verted This hs been clculted for the strtegy for wter iodiztion s whole. It ws not possible to differentite between the impct of school bsed strtegy nd household bsed strtegy s both the strtegies hve been strted simultneously in ll the plces. To clculte the effectiveness of wter iodiztion lone, dt from school children in the provinces of Me Hong Son, Uttrdit, nd Tk from 1990 to 1993 ws used (Ministry of Public Helth, 1992; 1993; Pisolybutr, 1994). We clculted the verge rte of decrese in the goiter rte per yer due to combined strtegy of wter nd slt iodiztion. The verge decline in the three provinces ws 2.36% (2.12 + 4.27 + 0.73 3). The selection of the provinces ws mde on the bsis of the existing prevlence eg more thn 40% in Me Hong Son nd Uttrdit nd more thn 20% in Tk Province. This ensured tht both high nd modertely endemic res, where wter iodiztion hs been implemented, were represented. This decrese of 2.36% in the goiter rte could be ttributble to combined strtegy of slt nd wter iodiztion. We then ssumed tht the individul impct of the two strtegies depended upon the complince with the two strtegies. The verge utiliztion of iodized slt by the household ws 92.2% nd verge iodized wter utiliztion ws 58.2% (Ministry of Public Helth, 1993). The rtio of impct ttributble to iodized slt vs iodized wter cme to 1.5:1 (92.2:58.2; 60:40). Hence, the impct ttributble to wter iodiztion lone ws 0.95% (40% of 2.36%). Assuming tht there ws 200 school children in the ge group 6-14 yers the number of goiter cses verted cme out to be 2 per yer. The totl cost of wter iodiztion ws estimted s 9,729 Bht (US$ 389). Thus the cost per goiter verted by combined strtegy of school nd household wter iodiztion strtegy is 4,864.5 Bhts (US$ 195). DISCUSSION Thilnd hs dopted three pronged strtegy for IDD control in the high endemic res so tht IDD cn be quickly reduced to level where it ceses to be public helth problem ie below 5%. This is only short term mesure to rech the unreched nd hrd to rech popultion groups. In mny plces, it hs helped to reduce the goiter rte substntilly. The household bsed wter iodiztion is low cost intervention s compred to the two school bsed intervention which hd similr costs. The cost estimtes rrived t in this study, would be useful in deciding the further course of ction in Thilnd. However, other issues re importnt in the decision mking which re discussed lter. There re some limittions of this study which need to be kept in mind. It my be noted tht, s of now, the exchnge rte for US$ is t 35 to 45 Bhts which is bout one nd hlf times tht of wht it ws in 1996 when the study ws conducted. This limittion hs to be kept in mind when mking interntionl comprisons. The study is bsed on limited observtions only. As the different IDD prevention progrms were implemented simultneously, ssessing effectiveness of wter iodiztion progrm ws difficult. However, lck of informtion on economic spects of IDD control mke this study worthwhile despite this limittion. Wter iodiztion progrm ppers to be low cost intervention. However, before this cn be recommended s strtegy, issues relted to sustinbility needs to be ddressed. Technicl sustinbility The vehicle used for iodine fortifiction should 767

be such tht it does not interfere with iodine vilbility. In cse of wter, especilly in north nd northest where goiter prevlence is high, the source of wter is rinwter, river, mountin reservoir etc. (Wnrtn 1994,b). This wter my be rich in orgnic content nd my need chlorintion. Both the orgnic mtter nd chlorine in the wter re likely to interfere with iodine levels. We re not wre of ny studies on the impct of these constituents on wter iodiztion. Mngeril nd behviorl sustinbility The three key fctors in the success of wter iodiztion progrm re the supply of potssium iodte solution (mngeril), dding the pproprite mount of iodine in drinking wter on dily bsis (behviorl) nd monitoring of iodine content of wter (mngeril). The key persons involved in the bove ctivities re service providers nd household members. Their effective nd continued involvement in this ctivity depends on their sttus of knowledge, skill nd motivtion. This rises the importnt issue of regulr procurement nd distribution of potssium iodte s per the requirement of the household/schools by the providers. For better complince, continuing eduction progrm for providers nd n pproprite IEC pckge for the consumers should be implemented. The success of ll these ctivities depends on effective monitoring on regulr bsis nd its feedbck into the system so tht corrective mesures cn be tken. Without this, the sustinbility of such n importnt progrm will be difficult. Finncil sustinbility Mking vilble finnces for ll the three strtegies is definitely problem. For the sme mount of effectiveness, the incrementl cost of improving one strtegy will usully be less thn the cost of dopting nother strtegy. The sustinbility issue is lso pplicble to the slt iodiztion progrm especilly s implemented in Thilnd. Currently, the distribution of iodized slt is hevily dependent on the helth system. Though such system is cceptble s short term mesure, cretion nd mintennce of prllel system of slt distribution my not be sustinble s long term mesure. The Ministry of Public Helth of Thilnd hs with gret determintion nd combintion of effective strtegies controlled IDD to significnt level. But, the importnt tsk of sustinbility lies hed. ACKNOWLEDGEMENTS This study ws funded by Interntionl Council for Control of Iodine Deficiency Disorders. We re grteful to The Government of Thilnd especilly the Division of Nutrition in the Ministry of Public Helth for their kind coopertion. REFERENCES Klerks 1957 s quoted by Ministry of Public Helth, 1992. Ministry of Public Helth. The control of iodine deficiency in Thilnd - pst, present nd future. Nutrition Division, Deprtment of Helth, Februry, 1992. Ministry of Public Helth. Study on complince of the popultion towrds iodine supplementtion mesure for control of Iodine Deficiency Disorders (Report of ssessment). Iodine Deficiency Disorders Control nd Prevention Section, Division of Nutrition, Deprtment of Helth, 1993. Ministry of Public Helth Report of the Second Ntionl IDD Seminr: Towrds the elimintion of IDD in Thilnd. Bngkok, Thilnd, 1994. Ministry of Public Helth. Thilnd Helth Profile: Thilnd 1996. Pisolybutr U. Evolution of nutrition in the helth development pln of Thilnd. Nutrition Division, Deprtment of Public Helth, Ministry of Public Helth, Mrch 1994. Pringpungko 1953 s quoted by Ministry of Public Helth, 1992. Rmlingswmi 1955 s quoted by Ministry of Public Helth, 1992. Wnrtn L. Iodted slt in Thilnd. Nutrition Division, Deprtment of Public Helth, Ministry of Public Helth, Mrch 1994. Wnrtn L. Nturl slt in Thilnd. Nutrition Division, Deprtment of Public Helth, Ministry of Public Helth, Mrch 1994b. 768