Epidemiology of Tuberculosis Infection in Children

Tuberculosis remains one of the major diseases afflicting children throughout the world. The World Health Organization (WHO) recommends tuberculosis disease screening in children who live in the household of a smear-positive case, but lack effective measures for this management in high-burden countries to perform this routinely. WHO has recently called for more studies to define the global epidemiology of childhood tuberculosis, because the literature remains scant, dominated primarily by studies from industrialized countries and South Africa, but few epidemiologic studies of pediatric tuberculosis have been published from Asia. Children account for 10-15% of all new cases of tuberculosis worldwide. For a long time, childhood tuberculosis was neglected because of the paucibacillary characteristic of the disease in pediatric population. However, recent works have reinforced the role of childhood tuberculosis as an indicator of the effectiveness of control-programmes and also in the dissemination of the disease, since prevalent cases may persist for a long time. This chapter will focus on epidemiologic parameters related to childhood tuberculosis, including risk factors associated to disease development, the extrapulmonary tuberculosis epidemiology and the limitations in children tuberculosis diagnosis, which impairs the correct evaluation of the impact of tuberculosis in childhood community.