title: Latent tuberculosis infection among undergraduate medical students in Rio de Janeiro State, Brazil.
abstract: METHODS
  Five medical schools in three cities with different tuberculosis (TB) incidence rates in Rio de Janeiro State, Brazil.
  
  
  OBJECTIVE
  To estimate prevalence of and associated factors for latent tuberculosis infection (LTBI) among medical students.
  
  
  METHODS
  A cross-sectional survey was conducted among undergraduate students in pre-clinical, early and late clinical years from schools in cities with low (28/100,000), intermediate (63/100,000) and high (114/100,000) TB incidence rates. Information on socio-demographic profile, previous BCG vaccination, potential TB exposure, co-morbidity and use of respiratory protective masks was obtained. A tuberculin skin test (TST) was performed using the Mantoux technique by an experienced professional. A positive TST, defined as induration > or = 10 mm, was considered LTBI.
  
  
  RESULTS
  LTBI prevalence was 6.9% (95%CI 5.4-8.6). In multivariate analysis, male sex (adjusted odds ratio [aOR] 1.8; 95% CI 1.1-3.0), late clinical years (aOR 1.9; 95% CI 1.01-3.5), intermediate TB incidence (aOR 4.3; 95% CI 1.3-14.6) and high TB incidence in the city of medical school (aOR 5.1; 95% CI 1.6-16.8) were significantly associated with LTBI.
  
  
  CONCLUSIONS
  The higher prevalence of LTBI in late clinical years suggests that medical students are at increased risk for nosocomial Mycobacterium tuberculosis infection. The implementation of a TB control program may be necessary in medical schools, particularly in cities with higher TB incidence.
authors.affiliation: Department of Internal Medicine, Gama Filho University, Rio de Janeiro, Brazil. elenygt@centroin.com.br
authors.forename: E G
authors.initials: EG
authors.lastname: Teixeira
authors.forename: D
authors.initials: D
authors.lastname: Menzies
authors.forename: G W
authors.initials: GW
authors.lastname: Comstock
authors.forename: A J L A
authors.initials: AJ
authors.lastname: Cunha
authors.forename: A L
authors.initials: AL
authors.lastname: Kritski
authors.forename: L C
authors.initials: LC
authors.lastname: Soares
authors.forename: E
authors.initials: E
authors.lastname: Bethlem
authors.forename: G
authors.initials: G
authors.lastname: Zanetti
authors.forename: A
authors.initials: A
authors.lastname: Ruffino-Netto
authors.forename: M T C T
authors.initials: MT
authors.lastname: Belo
authors.forename: L
authors.initials: L
authors.lastname: Selig
authors.forename: M M Castello
authors.initials: MM
authors.lastname: Branco
authors.forename: D
authors.initials: D
authors.lastname: Cherri
authors.forename: S
authors.initials: S
authors.lastname: Maia
authors.forename: R
authors.initials: R
authors.lastname: Marandino
authors.forename: R R
authors.initials: RR
authors.lastname: Luiz
authors.forename: R E
authors.initials: RE
authors.lastname: Chaisson
authors.forename: A
authors.initials: A
authors.lastname: Trajman
mesh_terms: D000328:Adult; D001938:Brazil; D003428:Cross Infection; D003430:Cross-Sectional Studies; D004504:Education, Medical, Undergraduate; D005260:Female; D006306:Health Surveys; D006801:Humans; D015994:Incidence; D017053:Infection Control; D008297:Male; D015995:Prevalence; D012307:Risk Factors; D013337:Students, Medical; D014397:Tuberculosis, Pulmonary / Q000453:epidemiology* / Q000635:transmission*