[Tuberculosis risk groups among children and principles of approach to chemoprophylaxis].

The trends in tuberculin reactions of Mantoux test (2 TU) performed annually before and after the diagnosis of tuberculosis shows that the risk groups consist of subjects with increasing tuberculin sensitivity and those susceptible to acute respiratory virus infections. An individual approach to prescription of chemoprophylaxis considering the number of risk factors (epidemiological, age-sex, biomedical, social) is advisable. Sanatorium chemoprophylaxis is needed in the presence of at least 2 factors. A 3-month isoniazid chemoprophylaxis prevents the disease and normalizes sensitivity to tuberculin.