title: Predictive factors for latent tuberculosis infection among adolescents in a high-burden area in South Africa.
abstract: METHODS
  A high tuberculosis (TB) burden area in South Africa (notification rate for all TB cases 1400 per 100 000 population).
  
  
  OBJECTIVE
  To determine the prevalence of and predictive factors associated with latent TB infection in adolescents.
  
  
  METHODS
  Adolescents aged 12-18 years were recruited from high schools, clinical and demographic data were collected, and a tuberculin skin test (TST) and a QuantiFERON®-TB Gold In-Tube (QFT) assay performed.
  
  
  RESULTS
  A total of 6363 (58.2%) of 10 942 adolescents at the schools were enrolled. After exclusions, of 5244 participants, 55.2% (95%CI 53.8-56.5) had TST ≥ 5 mm, while 50.9% (49.5-52.2) were QFT-positive. On multivariate analysis, Black/mixed race racial groups, male sex, older age, household TB contact, low income and low education level were predictive factors for both TST- and QFT-positive results.
  
  
  CONCLUSIONS
  About half of the adolescents were found to be latently infected with TB in a high TB burden area with demographic and poverty-related socio-economic factors predicting the risk of TB infection. Adolescents from deprived communities should be considered an important target group for educational interventions by TB control programmes in high-burden settings.
authors.affiliation: South African Tuberculosis Vaccine Initiative (SATVI), Institute of Infectious Disease and Molecular Medicine, University of Cape Town, Cape Town, South Africa.
authors.forename: H
authors.initials: H
authors.lastname: Mahomed
authors.forename: T
authors.initials: T
authors.lastname: Hawkridge
authors.forename: S
authors.initials: S
authors.lastname: Verver
authors.forename: L
authors.initials: L
authors.lastname: Geiter
authors.forename: M
authors.initials: M
authors.lastname: Hatherill
authors.forename: D-A
authors.initials: DA
authors.lastname: Abrahams
authors.forename: R
authors.initials: R
authors.lastname: Ehrlich
authors.forename: W A
authors.initials: WA
authors.lastname: Hanekom
authors.forename: G D
authors.initials: GD
authors.lastname: Hussey
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D004522:Educational Status; D005260:Female; D006801:Humans; D007371:Interferon-gamma / Q000097:blood*; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000453:epidemiology; D008297:Male; D011203:Poverty; D011237:Predictive Value of Tests; D015995:Prevalence; D044469:Racial Groups; D012737:Sex Factors; D012959:Socioeconomic Factors; D013019:South Africa / Q000453:epidemiology; D014374:Tuberculin Test / Q000379:methods*
chemical_list: D007371:Interferon-gamma