One in every 3,500 new-born babies worldwide is affected by a thyroid deficiency. Up to 1 in 900 babies are born with this deficiency in regions with low iodine diets. If the disease is detected within the earliest days of life and the child is treated promptly with a hormonal replacement, it will grow up to be normal and healthy. Proper detection requires screening all new-borns. So over the past 10 years, the International Atomic Energy Agency (IAEA) has been supporting national and regional screening programs in more than 20 developing countries in Africa, Asia and Latin America, using the Radioimmunoassay (RIA) technique.