title: Human immunodeficiency virus associated tuberculosis more often due to recent infection than reactivation of latent infection.
abstract: BACKGROUND
  It is unclear whether human immunodeficiency virus (HIV) increases the risk of tuberculosis (TB) mainly through reactivation or following recent Mycobacterium tuberculosis (re)infection. Within a DNA fingerprint-defined cluster of TB cases, reactivation cases are assumed to be the source of infection for subsequent secondary cases. As HIV-positive TB cases are less likely to be source cases, equal or higher clustering in HIV-positives would suggest that HIV mainly increases the risk of TB following recent infection.
  
  
  METHODS
  A systematic review was conducted to identify all studies on TB clustering and HIV infection in HIV-endemic populations. Available individual patient data from eligible studies were pooled to analyse the association between clustering and HIV.
  
  
  RESULTS
  Of seven eligible studies, six contributed individual patient data on 2116 patients. Clustering was as, or more, likely in the HIV-positive population, both overall (summary OR 1.26, 95%CI 1.0-1.5), and within age groups (OR 1.50, 95%CI 0.9-2.3; OR 1.00, 95%CI 0.8-1.3 and OR 2.57, 95%CI 1.4-5.7) for ages 15-25, 26-50 and >50 years, respectively.
  
  
  CONCLUSIONS
  Our results suggest that HIV infection mainly increases the risk of TB following recent M. tuberculosis transmission, and that TB control measures in HIV-endemic settings should therefore focus on controlling M. tuberculosis transmission rather than treating individuals with latent M. tuberculosis infection.
authors.affiliation: Infectious Disease Epidemiology Unit, London School of Hygiene & Tropical Medicine, London, UK. Rein.Houben@lshtm.ac.uk
authors.forename: R M G J
authors.initials: RM
authors.lastname: Houben
authors.forename: A C
authors.initials: AC
authors.lastname: Crampin
authors.forename: R
authors.initials: R
authors.lastname: Ndhlovu
authors.forename: P
authors.initials: P
authors.lastname: Sonnenberg
authors.forename: P
authors.initials: P
authors.lastname: Godfrey-Faussett
authors.forename: W H
authors.initials: WH
authors.lastname: Haas
authors.forename: G
authors.initials: G
authors.lastname: Engelmann
authors.forename: C J
authors.initials: CJ
authors.lastname: Lombard
authors.forename: D
authors.initials: D
authors.lastname: Wilkinson
authors.forename: J
authors.initials: J
authors.lastname: Bruchfeld
authors.forename: S
authors.initials: S
authors.lastname: Lockman
authors.forename: J
authors.initials: J
authors.lastname: Tappero
authors.forename: J R
authors.initials: JR
authors.lastname: Glynn
mesh_terms: D000293:Adolescent; D000328:Adult; D000367:Age Factors; D016000:Cluster Analysis; D019353:Endemic Diseases / Q000517:prevention & control; D005260:Female; D015658:HIV Infections / Q000453:epidemiology*; D006801:Humans; D055985:Latent Tuberculosis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology / Q000635:transmission; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000472:pathogenicity*; D016017:Odds Ratio; D018570:Risk Assessment; D012307:Risk Factors; D014376:Tuberculosis / Q000175:diagnosis / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission; D014775:Virus Activation; D055815:Young Adult