Globally, infectious diseases are responsible for more than two-thirds of the estimated 12 million deaths annually in children under five years of age. Current delivery of immunisation services prevents three million deaths worldwide (1). Many more deaths can be prevented by optimal use of existing vaccines. Childhood pneumonia and diarrhoea are the number one and number two killers in children in the developing world. New vaccines have just been introduced against Streptococcus pneumoniae, which would prevent deaths due to pneumonia. These new conjugate vaccines are expensive. A look at where we are in prevention of some of these diseases may help to make immunisation priorities clearer.
Iodine is a trace element present in small quantities in the human body. It is required for the synthesis of thyroid hormones by the thyroid gland and this is its only confirmed role. Therefore, populations living in an iodine-deficient area are at high risk of impaired thyroid hormonogenesis and, if iodine deficiency is severe enough, hypothyroidism and endemic goiter (Figure) and cretinism. The consequences of iodine deficiency may be especially severe in the fetus and the neonate.
Pica is an eating disorder involving the compulsive, irrational ingestion of nutrient or non-nutrient substances over a sustained period of time. Geophagia is the most common pica in children. Other substances ingested include clay, earth, soil, paper, ice cubes, raw rice, etc.