Surveillance on Iodine Deficiency Disorders in Longitudinal Surveillance Sites of Chongqing City in 2012

Objective To understand the prevention and control effects of iodine deficiency disorders and its progression trend of disease condition in Chongqing. Methods One primary school was randomly selected as longitudinal surveillance sites in each of 4 counties in Chongqing city. A total of 90 children aged 8 to 10 years were randomly selected in each school with goiter, salt iodine, urinary iodine and intelligence detected. Meanwhile, in the four sites, urinary iodine of pregnant women and nursing women was tested. The goiter was examined by B-ultrasonograghy, urinary iodine by Ce arsenic acid digestion, and salt iodine by direct drop methods. Results A total of 360 children aged 8 to 10 years were investigated surveillance sites. The total goiter rate was 5.28%. There was no significant difference in the total goiter rate among different counties(P0.05). The median of iodized salt was 26.65 mg/kg. The coverage rate of iodized salt, consumption rate of qualified iodized salt and intake rate of qualified iodized salt was 99.72%, 91.09% and 97.04%, respectively. The medians of urine iodine of children, pregnant and nursing women were 238.15 μg/L, 218.15 μg/L and 252.90 μg/L, respectively. The cases with urine iodine lower than 100 μg/L accounted for 11.94%, 32.93% and 13.75%, respectively. The cases with urine iodine above 300 μg/L accounted for 34.17%, 13.41% and 43.75%, respectively. The mean intelligence quotient of children was 112.57. Conclusion The goiter rate of schoolchildren in Chongqing city is relatively high and the population's iodine nutrition level is stable. However, the shortage and overdose of iodine still exist in Chongqing city.