title: Role of QuantiFERON-TB-Gold In Tube assay for active and latent tuberculosis infection in investigation of tuberculosis outbreak in a university.
abstract: BACKGROUND
  Identification and monitoring of active tuberculosis (TB) and latent tuberculosis infection (LTBI) are the key steps to prevent transmission during a TB outbreak. The aim of this study was to evaluate the role of QuantiFERON-TB-Gold In Tube assay (QFT-GIT) in the investigation of active TB and LTBI cases during a TB outbreak in a university.
  
  
  METHODS
  In this study, enrolled students and teachers were evaluated with chest radiograph, questionnaire, and QFT-GIT test. The diagnosis of active pulmonary TB was based on sputum studies and chest radiographs. The questionnaire, which covered demographic information, underlying diseases, and environmental exposures, was applied to assess the association of risk factors by multiple logistic regressions.
  
  
  RESULTS
  A total of 159 participants completed the study protocol. Positive QFT-GIT results were demonstrated in class A (75.7%; 25/33), class B (57.1%; 20/35), and class C (37.5%; 3/8) in institute 1; class D (17.3%; 8/46) in institute 2; and class E (3.1%; 1/32) in institute 3; but none among the (0/5) administrative officers, who comprised the control group. "Number of contact with active TB cases" was strongly associated and correlated with the prediction of a positive QFT-GIT result in multivariate analysis (odds ratio = 1.99; 95% confidence interval, 1.52-2.61; p < 0.0001). Seven cases progressed to active TB infection, all showing positive QFT-GIT results (100%; 7/7).
  
  
  CONCLUSIONS
  Inclusion of QFT-GIT may be helpful in controlling and monitoring of active TB and LTBI cases during an investigation of a TB outbreak. The finding demonstrated that the QFT-GIT test was useful in accurately identifying infected and uninfected students, permitting rapid intervention.
authors.affiliation: Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan; Division of Infectious Diseases, Department of Internal Medicine, Kaohsiung Armed Forces General Hospital, Kaohsiung, Taiwan.
authors.forename: Chen-Yu
authors.initials: CY
authors.lastname: Li
authors.affiliation: School of Public Health, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Hsieng-Ching
authors.initials: HC
authors.lastname: Chen
authors.affiliation: School of Public Health, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Hsin-Yi
authors.initials: HY
authors.lastname: Cheng
authors.affiliation: Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Chih-Feng
authors.initials: CF
authors.lastname: Chian
authors.affiliation: Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan; Graduate Institute of Medical Sciences, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Feng-Yee
authors.initials: FY
authors.lastname: Chang
authors.affiliation: National Defense Medical Center and Chang Jung Christian University Taipei, Taiwan.
authors.forename: Hong-I
authors.initials: HI
authors.lastname: Chen
authors.affiliation: School of Public Health, National Defense Medical Center, Taipei, Taiwan.
authors.forename: Chih-Hung
authors.initials: CH
authors.lastname: Ku
authors.affiliation: Division of Infectious Diseases and Tropical Medicine, Department of Internal Medicine, Tri-Service General Hospital, National Defense Medical Center, Taipei, Taiwan. Electronic address: jclin@ndmctsgh.edu.tw.
authors.forename: Jung-Chung
authors.initials: JC
authors.lastname: Lin
mesh_terms: D000328:Adult; D003955:Diagnostic Tests, Routine / Q000379:methods*; D004196:Disease Outbreaks; D005260:Female; D006801:Humans; D059425:Interferon-gamma Release Tests / Q000379:methods*; D008297:Male; D013902:Radiography, Thoracic; D011795:Surveys and Questionnaires; D014376:Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology*; D014495:Universities; D055815:Young Adult
keywords: Latent tuberculosis infection; Outbreak; QFT-GIT; Tuberculosis