Analysis of national surveillance results on iodized salt in non-high iodine areas in 2015 / 中华地方病学杂志

ABSTRACT

Objective To study the current prevention and control status of iodine deficiency disorders (IDD) and learn the current situation of iodized salt consumption at household level in non-high iodine areas in 2015,this surveillance was conducted.Methods In 2015,according to National Surveillance Program on Iodine Deficiency Disorders,the surveillance was conducted at county level in 31 provinces,municipalities,autonomous regions (provinces) and Xinjiang Production and Construction corps (Xinjiang Corps).In each county city,district,banner (county),5 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;15 households were randomly selected in each chosen village.Edible salt sample was collected from each household.The iodine level in salt was determined by direct titration;the salt samples from Sichuan and other enhanced salt samples were detected by arbitration.Results There were totally 2 840 counties that reported the surveillance data.In total,849 193 salt samples were examined,including 845 906 salts determined by direct titration and 3 287 samples determined only by semi-quantitative detection.Weighted by population,the national coverage rate of iodized salt was 98.37％.At provincial level,the coverage rate of iodized salt was higher than 95％ except Tianjin,Shanghai and Shandong.At county level,2 669 counties had a coverage rate of iodized salt higher than or equal to 95％,171 counties were lower than 95％,and 31 counties were less than 80％.The national consumption rate of qualified iodized salt was 94.57％ (except 11 counties in Tibet).At provincial level,the consumption rate of qualified iodized salt was higher than 90％ except Shanghai (66.84％),Tianjin (79.14％),Tibet (82.09％) and Qinghai (89.22％).At county level,totally 2 633 counties had a rate of qualified iodized salt higher than 90％,and 196 counties were lower than 90％.The mean of iodine content in iodized salt was (25.37 ± 4.57) mg/kg.At provincial level,the means of iodine content in iodized salt were in the range of 23.51-28.95 mg/kg and the variable coefficient (CV) was in the range of 12.17％-27.37％,the CV was higher than 15％ in 24 provinces and Xinjiang Corps.Conclusions The coverage rate of iodized salt and the qualified iodized salt at national level are in a good condition.However,the problem of non-iodized salt is still serious in some provinces.