[The Case of a Tuberculosis Outbreak and Response at A Psychiatric Hospital in Daegu Metropolitan City]

Tuberculosis is an infectious disease caused by Mycobacterium tuberculosis and transmitted via the respiratory tract. When an infectious tuberculosis case arises in a group facility, an epidemiological investigation is conducted to identify contacts and detect active tuberculosis or latent tuberculosis infections (LTBI). In February 2023, a tuberculosis patient was reported from a psychiatric hospital in Daegu Metropolitan City. Through field investigations, the tuberculosis epidemiology investigation team identified 2 additional tuberculosis cases and 54 LTBI cases, confirming an outbreak. Follow-up investigations revealed two more tuberculosis cases among individuals previously diagnosed with LTBI, and an additional two tuberculosis cases were identified through routine surveillance. Evidently, all subsequent tuberculosis cases emerged among contacts who were identified during the initial field investigation. The outbreak was traced to a single tuberculosis patient, who had been present in the psychiatric hospital-a high-risk facility-for over 18 months. Genotype testing of culture-positive patients confirmed the same tuberculosis strain, linking all cases to the index patient. Psychiatric hospitals, as infection-prone environments, require robust control measures, including the prompt identification and treatment of both active tuberculosis and LTBI cases, to prevent further transmission.