An Outbreak of Isoniazid-Resistant Tuberculosis in a School Originating from Household Transmission - Guigang City, Guangxi Zhuang Autonomous Region, China, November 2024.

Tuberculosis (TB) represents one of the world's most significant infectious diseases, caused by Mycobacterium tuberculosis (M. tuberculosis). The pathogen spreads readily among students due to crowded environments and prolonged close contact during school activities. This outbreak investigation identified 18 TB cases (15 students, 1 teacher, and 2 staff members), including 5 cases with isoniazid-resistant TB. Sixteen pulmonary TB cases demonstrated clear epidemiological linkage, indicating a clustered outbreak spanning multiple households, school grades, and both junior and senior high schools. This outbreak underscores the critical importance of comprehensive household contact screening. When tuberculosis emerges within a family unit, school contacts - particularly students and teachers - require immediate and thorough screening. Additionally, the outbreak reveals significant gaps in the effectiveness and quality of entrance physical examinations that demand urgent improvement.