Analysis of a national surveillance results of iodized salt in 2008 / 中国地方病学杂志

Objective To study the national surveillance results and learn the current situation of iodized salt consumption at household level in 2008, and to find out the remaining problems and to provide scientific basis for developing control strategies against iedine deficiency disorders. Methods In 2008, in accordance with the requirements of the "National Iodine Deficiency Disorders Surveillance Program (Trial)", the surveillance was conducted at county level in 31 provinces and at division level in Xinjiang Production and Construction Corps. In each county 9 townships were randomly selected according to their sub-area positions of east, west, south, north and center;4 villages were randomly sampled in each chosen township;8 households were randomly selected in each chosen village. In every county with 9 or less townships, 1 township was randomly selected respectively in the east, west, south,north and center sub-areas;4 villages were randomly sampled in each chosen township;15 households were randomly selected in each chosen village. Edible salt from these households was collected. Iodized salt coverage rate, proportion of qualified iodized salt and consumption rate of the qualified iodized salt of the households in each province were counted and analyzed. Iodized salt was determined by direct titration;the salt samples from Sichuan and other enhanced salt were detected by arbitration. Results Totally 2817 counties (districts, cities, banners) and 14 divisions of the Xinjiang Production and Construction Corps reported the monitoring results, monitoring coverage reached 99.96%(2831/2832). Mean of iodine content was 31.51 mg/kg.Sixteen provinces had a variation coefficient of iodine content for more than 20%. A total of 826 968 households were tested of their edible salt, in which iodized salt 798 725 copies, non-iodized salt 28 243 copies, and unqualified iodized salt 20 270 copies. Weighted by population,at national level, the coverage rate of iodized salt was 97.48%, qualified rate of iodized salt 97.16%, and consumption rate of qualified iodized salt was 94.79%.Twenty seven provinces (autonomous regions and municipalities) and Xinjiang Production and Construction Corps had a qualified iodized salt coverage rate of above or equal 90.00%. Tibet, Hainan, Xinjiang and Tianjin provinces (regions) had a qualified iodized salt coverage rate lower than 90.00%. Further, 2487 counties had the rate high or equal 90.00% accounting for 87.82% (2487/2831) of complementing monitoring counties. One hundred and four counties and 1 division of the Xinjiang Production and Construction Corps had the coverage rate of iodized salt below 80.00%. Conclusions Sixteen provinces(autonomous regions and municipalities) have relatively a high degree of variation coefficient in salt iodine content. The quality of iodized salt needs to be improved. The coverage rate of iodized salt and the qualified iodized salt at national level are both above or equal 90.00%. However, the non-iodized salt problem is still serious and have a relatively lower coverage of iodized salt in Tibet, Hainan and Xinjiang.

Monitoring data analysis of iodized salt of national key sample in China in 2008 / 中国地方病学杂志

Objective To understand the current level of iodized salt coverage in areas with intensified monitoring measure in China in 2008. Methods In accordance with the "National Iodine Deficiency Disorders Surveillance Program (Trial)" of Ministry of Health issued in 2007, the selected key counties (cities, districts and banner) were divided into 5 sub-areas, 1 non-iodine townships(towns, street offices) was sampled randomly in each sub-area, 4 administrative villages (neighborhood committees) were sampled from each selected township;15households salt samples in each selected village were randomly collected. All salt samples were detected by semiquantitative kit at first. The salt samples that can not be determined by the kit were tested by direct titration and the arbitration act (GB/T 13025.7-1999) detection. Iodized salt determination criteria: reagent color change in semiquantitative test kit or iodine content ≥ 5 mg/kg were identified as iodized salt. Otherwise, the salt samples were identified as non-iodized salt. Results All the provinces(autonomous regions, municipalities) except Tibet in China had conducted a specific survey on iodized salt coverage in non-iodized salt high-risk areas, which revealed that the national coverage rate of iodized salt was 93.01%(130 928/140 770). At the provincial level, twenty provinces and the Xinjiang Production and Construction Corp had a iodized salt coverage over 90%, while the other six provinces (Beijing, Xinjiang, Zhejiang, Fujian, Tianjin and Jiangxi) between 80% - ＜ 90% and the rest four provinces,such as Guangxi, Qinghai, Guangdong and Hainan, lower than 80%. At the county level, 64.57%(277/429) of all the surveillance counties had a iodized salt coverage over 95% while 10.02%(43/429) lower than 80%. Among all the six types of areas where specific survey were conducted, areas with incomplete iodized salt distribution network and areas with crude salt production had a iodized salt coverage lower than 90%, 81.74%(4978/6090) and 86.53%(17 098/19 759), respectively. In raw salt production area, there were 10 out of 21 provinces with iodized salt coverage rate below 90%, it consisted of 47.6%(10/21) of the total monitoring provinces in the same type areas.There were 8 out of 16 provinces with iodized salt coverage rate lower than 90% in the areas with faultiness iodized salt network, it consisted of 50.0%(8/16) of the sampling provinces in the same type area. Conclusions Most provinces(21) in China have a relatively high iodized salt coverage at household level during this specific survey.Areas with incomplete iodized salt distribution network and crude salt production are the most affected areas by noniodized salt. Aiming at the high-risk non-iodized salt areas discovered during this survey, corresponding intervention measures should be implemented with joint efforts from sectors concerned.

Study of universal salt iodization on child intellectual quotient development in Hainan province / 中国地方病学杂志

Objective To estimate the impact of universal salt iodization on child intelligence quotient (IQ) development in Hainan province. Methods In this is a cross-section study from September in 2008 to April in 2009,the observation group was historical iodine deficiency ward which includes 2 counties and 6 townships,and the control group was non-historical ward which includes 6 counties and 9 townships. Comparison of child IQ distribution according to different geographical housing position(plain,mountainous area,coast),age and sex based on the result of urine iodine examination and the IQ test of children between 8 and 10 years old. Results The median of urinary iodine of children in the observation group was 196.2μg/L which was 2.13 times of the urinary iodine median in the control group(91.9μg/L). The average IQ of children in the observation group was 94.7 which was 8.5 higher than the control group(86.2) ; IQ≤69 rate in this group was 7.7%(91/1179),and it was 8.9 percentage point lower than the control group[16.6%(253/1520)]; IQ≥ 110 rate of the group was 18.3%(216/1179),and it was 10.0 percentage point higher than the control group[8.3%(126/1520)]. The average IQ of children living in mountainous area(83.1) was the lowest in the control group. It was 3.5 and 5.1 lower than that of the children living in the plain(86.6) and coastal area(88.2) respectively; the IQ≤69 rate of children living in mountainous area [20.5%(91/443)]was the highest,and it was 3.8 and 7.1 percentage point higher than that of the children living in the plain [16.7% (89/533)]and coastal areas [13.4% (73/544)]respectively. The average IQ of children aged 8 (97.4) was similar to those aged 9(95.9) in the observation group which was 6.8 and 5.3 higher than that of the children aged 10(90.6) in the same group respectively; However,the average IQ of children aged 8,9 and 10 was close in the control group(86.8,86.3 and 85.6). The average IQ of boys(96.2) was 3.1 higher than that of the girls(93.1),and their IQ≤69 rate[6.3%(37/590)]was 2.9 percentage point lower than that of the girls[9.2% (54/589)]in the observation group. On the other hand,the average IQ(87.2) of boys was 2.1 higher than that of the girls(85.1),and IQ≤69 rate[14.5%(114/787)]was 4.5 percentage point lower than that of the girls [19.0%(139/733)]in the control group. The average IQ of children with different housing geographical position,age and sex in observation group was 5.0-12.4 higher than that of the control group; their IQ≤69 rate was 7.7-13.2 percentage point lower than that of the control group; their IQ≥110 rate was 5.6-13.0 percentage point higher than that of the control group. Conclusions Supplementing salt iodization can improve child intelligence. Supplementing iodine can increase the child IQ and reduce the child mental retardation.

Surveillance on iodized salt in China, in 2006 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the national situation of quality and consumption of iodized salt at production and household levels.</p><p><b>METHODS</b>Detailed surveillance method could be found in 'national iodized salt surveillance scheme', issued by MOH in 2004. The iodine concentrations in salt (except some special kinds of salt) were detected by direct titration with national standard of GB/T 13025.7-1999, in which the iodine content in qualified iodized salt was set as between 20 and 50 mg/kg and that in non-iodized salt was set as below 5 mg/kg.</p><p><b>RESULTS</b>At production level, the national lot qualified rate was 98.36% and all the provincial lot qualified rate of production level was over 90%. At household level, the national iodized salt coverage rate of household was 96.87% and the national qualified iodized salt coverage rate was 93.75%. 4 provinces (Tibet, Hainan, Xinjiang and Guangdong) had an iodized salt coverage rate lower than 90%. Further, the qualified iodized salt coverage rate of 5 provinces (Tibet, Hainan, Xinjiang, Guangdong and Qinghai) was below 90%. In 2006,80 counties did not conduct the iodized salt surveillance and non-iodized salt coverage rate of 185 counties was higher than 10%. In the respect of the qualified iodized salt coverage rate at household level, there were about 10 percent lagging behind the national goal that 95% of all the counties in China should achieve virtual elimination of iodine deficiency disorder before 2010.</p><p><b>CONCLUSION</b>At national level,the lot qualified rate at production level and the iodized salt coverage rate at household level maintained comparatively well. However, at county level, there were 75 counties whose iodized salt coverage rate was below 70%.</p>

Analysis on the progress and problems in controlling iodine deficiency disorders in Xinjiang Autonomous Region / 中国地方病学杂志

Objective To evaluate the effectiveness of the comprehensive intervention program of Xinjiang and to analyze the main problems to provide references for the adjusting on the intervention strategies in future work.Methods Based upon the combination of reviewing literatures,field investigations and questionnaires,an overall evaluation was made on the effectiveness of the program,supportive policies and intervention measures,etc.Results Some progressions had been achieved in the early days.However,in recent years,the negligence of the work and failed coordination between the related governments,and unbenefitting policies for iodinated salt,were the main obstacles for the progress.Conclusions To improve the progress of controlling iodine deficiency disorders,the government should fully carry on its responsibility,giving supports both of policy and funds.Salt administrative sector should make favourable policies to benefit the local population.And health sector should coordinate the related sectors,and reinforce the health education and surveillance.

A pilot study on the feasibility of simplified scheme of national iodized salt monitoring program / 中华流行病学杂志

<p><b>OBJECTIVE</b>To draft out the simplified scheme of iodized salt monitoring program to compare with the current scheme, and to study its feasibility.</p><p><b>METHODS</b>8 counties from 4 provinces were selected at different coverage rate of iodized salt. Conduct the monitoring program using the current scheme and the simplified scheme, then compare the results.</p><p><b>RESULTS</b>The monitoring results of the current scheme showed the coverage rate of iodized salt and adequate iodized salt were 88.1% and 84.8% and the data of the simplified scheme were 85.2% and 79.8% respectively. Five counties reached above 90% of both the coverage rates of iodized salt and adequate iodized salt and the results showed no significant difference between the two schemes. The rates of other three counties were low, and the difference was significant between Dulan and Linxia counties. To the whole samples, the difference was also significant.</p><p><b>CONCLUSION</b>The simplified scheme could be applied to those that the coverage rate of iodized salt was quite high or the non-iodized salt was well-distrbuted. However, for those areas with low coverage rate, it might not be suitable. As for the whole nation, it might not be popularized due to the gap of coverage rate between western and eastern areas.</p>

Study on the national program of monltoring the iodized-salt situation in 2004 / 中华流行病学杂志

<p><b>OBJECTIVE</b>To understand the situation of quality and consumption of iodized-salt at production and household levels through monitoring on salt.</p><p><b>METHODS</b>9 townships were chosen in each county at different locations. In each township, two villages were selected in the center of the township and another two villages in remote settings. In each village, 8 households were selected for salt collection. The iodine concentrations in salt (except some special kinds of salt) were detected by method of direct titration with criteria in GB/T 13025.7-1999, in which the iodine content in qualified iodized-salt was set as 20 to 50 mg/kg and that in non-iodized-salt it was below 5 mg/kg.</p><p><b>RESULTS</b>Except for Tibet and Xinjiang, lot qualified rate of production level was 97.39% at the national level. Except for Xinjiang, the qualified rate of iodized-salt of household level was 96.45%; qualified iodized-salt coverage rate was 93.47%; noniodized-salt coverage rate was 3.09%. The results of the iodized-salt monitoring in 2004 maintained almost the same level as that in 2002. At production level,lot qualified rate of iodized-salt in Sichuan and Qinghai provinces were below 90%. At household level the qualified rate of iodized-salt in Sichuan and Hainan were below 90%. The coverage rates of qualified iodized-salt were below 90% for the total 7 provinces. In 5 provinces, the non-iodized-salt coverage rates were above 10%.</p><p><b>CONCLUSIONS</b>At national level the qualification of iodized-salt at production level was satisfactory. The coverage rates of qualified iodized-salt were below 90% not only in western but in some eastern provinces(including Beijing), which indicated that importance should be attached to the western areas and some newly discovered areas with problems as well. Through continual improvement of qualified iodized-salt coverage, sustained IDD elimination will be achieved.</p>