High rate of transmission in a pulmonary tuberculosis outbreak in a junior high school in China, 2020

Abstract Background : School tuberculosis outbreak is common in China. This study aims to introduce a new screening process to control outbreak. Methods : We conducted an epidemiological investigation to identify the origin of the outbreak and how it was transmitted. Results : A total of 10 confirmed active tuberculosis cases were diagnosed with an overall rate of disease attack was 19.2%(10/52) in the same class as the index case. 3 were found through a proactive visit and 7 were through screening. Of the 9 secondary cases, 2 had purified protein derivation of tuberculin(PPD)≥15mm or blister (confirmed by computerized tomography(CT) scan before having preventive therapy), 5 had TST≥10 and Conclusion : Through this special school outbreak, we recommend a new screening process that conducting Interferon-Gamma Release Assays test on those students with PPD≥5mm and