title: Latent tuberculosis infection is prevalent among socially marginalised citizens in Aarhus, Denmark.
abstract: BACKGROUND
  Even in low-incidence countries, tuberculosis (TB) is common among socially marginalised people. Latent tuberculosis infection (LTBI) comprises a reservoir for future disease, and screening for LTBI and TB in these groups aids in the prevention and early detection of TB.
  
  
  METHODS
  We performed a screening for LTBI with interferon gamma release assay (IGRA) testing, and TB screening with sputum smear examination at four shelters and four additional locations in a Danish urban area. Additionally, shelter volunteers were offered examination.
  
  
  RESULTS
  A total of 145 subjects were tested; 124 with sputum smear and 100 with IGRA. Overall, 13 (13%) had LTBI, and one (0.8%) had smear-negative, culture-positive, non-cavitating TB. Among 107 socially marginalised citizens, persons of Greenlandic origin had significantly more LTBI (40.0%) than Danish subjects (9.1%) (odds ratio (OR) = 6.67 (range: 1.55-28.63)), and other ethnicities had an intermediate prevalence of LTBI (18.2%) (OR versus Danish subjects = 2.22 (range: 0.35-14.06)). A total of 38 shelter volunteers were also included; IGRA was performed in 30 of those and one (3.33%) had LTBI.
  
  
  CONCLUSIONS
  Our results confirm that a screening approach may reveal early cases of active TB. LTBI is common among the socially marginalised people, but varies substantially with ethnic origin.
  
  
  BACKGROUND
  T-spot.TB kits were provided by Oxford Immunotec.
  
  
  BACKGROUND
  not relevant.
authors.affiliation: ninabreinholt@gmail.com.
authors.forename: Nina Breinholt
authors.initials: NB
authors.lastname: Stærke
authors.forename: Ole
authors.initials: O
authors.lastname: Hilberg
authors.forename: Christian
authors.initials: C
authors.lastname: Wejse
authors.forename: Hans Jürgen
authors.initials: HJ
authors.lastname: Hoffmann
authors.forename: Andreas
authors.initials: A
authors.lastname: Fløe
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D003718:Denmark / Q000453:epidemiology; D005260:Female; D006801:Humans; D015994:Incidence; D055985:Latent Tuberculosis / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D015995:Prevalence; D012189:Retrospective Studies; D014374:Tuberculin Test; D014505:Urban Population; D055815:Young Adult