A Pulmonary Tuberculosis Cluster in An Institution in Southern Taiwan, 2012

Wei-Tao Shen, Pei-Ling Lee, Huai-Te Tsai, Jen-Te Wang, Pi-Long Liu

2015 Vol.31 NO.6

Correspondence Author: Wei-Tao Shen

  • Southern Regional Center, Centers for Disease Control, Ministry of Health and Welfare, Taiwan


A mental institution resident in Southern Taiwan was ill and sought medical service in March 2014; later was confirmed as pulmonary tuberculosis (TB). Two contacts were found having abnormal chest radiography at the twelfth month and were notified. In July 2013, there were six reported probable patients with pulmonary tuberculosis from the institution including the index case. Five of them were confirmed, and one was excluded. Restriction fragment length polymorphism (RFLP) molecular study done at the Research and Diagnostic Center of Taiwan CDC revealed that the five isolates belonged to the same subtype, thus, proved this cluster of patients with pulmonary tuberculosis.

After two serial meetings with TB specialists, not only chest radiographies of related contacts were followed, but also extended the immunoassay from the previous existing tuberculin skin test (TST) to both interferon-gamma release assay (IGRA; QuantiFERON-TB, QFT) and TST for those identified contacts. After evaluation by physicians, the contacts who had both positive results of TST and IGRA were undergone latent tuberculosis infection (LTBI) treatment.

Besides, we suggested the administrator keeping the confirmed TB patients in the isolation room on the first floor until his/her sputum was negative for acid-fast stain or TB culture, and also to isolate those suspected TB patients.

Of total 85 contacted people, the positive rate of TST was 77.6% (66/85), the positive rate of QFT was 29.5% (18/61), and the positive rate for both TST and QFT was 21.2% (18/85). Twenty-four people underwent LTBI treatment, of whom 22 people completed the treatment course, and 2 people discontinued due to the adverse effects. There was not any tuberculosis patient found in the institution by October 2014.

Keywords:Tuberculosis;Populous institutions;Cluster infection;Contact;Treatment for latent tuberculosis infection (LTBI)