Active Screening of Latent Tuberculosis Infection in School Contacts of Active Tuberculosis Patients

The goal of this observational study is to investigate the proportion of Mycobacterium tuberculosis (MTB) infection in school contacts of active tuberculosis (ATB) patients. The main questions it aims to answer are:

* the proportion of MTB infection among school contacts of ATB patients * risk factors related to tuberculosis (TB) infection * health economic evaluation of screening strategy