[Childhood tuberculosis: an ancient disease in the youngest generation in the 21st century from epidemiological point of view].

Childhood tuberculosis (TB) has distinct epidemiological and clinical features. TB burden in children worldwide and in Croatia, the risk of infection and disease, as well as disease characteristics, sources of infection in children, diagnostic difficulties, impact of HIV on pediatric tuberculosis, limits of BCG-vaccine and program implications are discussed in this paper. Children younger than 15 years account for 15%-20% of global TB burden, which is often associated with severe TB-related morbidity and mortality. Childhood TB is rarely sputum-smear positive on microscopy. That is probably the reason for the lower priority traditionally given to children by TB control programs compared to that of adult disease. Young children are at a high risk of rapid progression from infection to disease, reflecting recent transmission rather than secondary reactivation. Therefore, the pediatric burden potentially provides a useful measure of current transmission within a community and it is a good indicator of the efficacy of TB control achieved in a particular community. Strict contact tracing and use of preventive chemotherapy is important to reduce TB-related suffering of children. Untreated latent TB infection in children provides the seed of the epidemic for the next generation. Evidence of an adult TB index case is a clue for diagnosis of childhood TB in low-endemic countries. Prognosis of early detected and properly treated TB is excellent. Consequently, new diagnostic methods and treatment options are an imperative. Among HIV-coinfected children, the optimal timing for highly active antiretroviral therapy initiation and drug combinations that have minimal interactions with anti-TB drugs need to be further explored. The most effective vaccine, suitable even for HIV-infected children, remains the need for successful prevention at the global level. The Stop TB Strategy, which builds on the previous Directly Observed Treatment Short-Course Strategy (DOTS) developed by the World Health Organization, has a critical role in reducing the worldwide burden of the disease and thus in protecting children from infection and disease. The management of children with TB should be in line with the Stop TB Strategy, taking into consideration the particular epidemiology and clinical presentation of TB in children. In addition to reducing the burden of adult TB, attention to childhood nutrition and improvement of socioeconomic conditions of communities is likely to have an impact on TB transmission to children.