title: Global incidence of multidrug-resistant tuberculosis.
abstract: BACKGROUND
  The global number of incident cases of multidrug-resistant (MDR) tuberculosis (TB) in 2000 was estimated to be 272,906 (95% confidence interval [CI], 184,948-414,295). For accurate planning of TB control programs, this estimate and others have been revised using data from additional countries and by including in the model previously treated TB cases, which had not been accounted for in the previous analysis.
  
  
  METHODS
  Multiple logistic regression was used to identify variables that were predictive of MDR-TB frequency among new and previously treated cases surveyed in 90 and 77 countries, respectively. These variables were then used to estimate MDR-TB frequencies in countries that had not been surveyed.
  
  
  RESULTS
  The total number of MDR-TB cases estimated to have occurred worldwide in 2004 is 424,203 (95% CI, 376,019-620,061), or 4.3% (95% CI, 3.8%-6.1%) of all new and previously treated TB cases. In the same year, 181,408 (95% CI, 135,276-319,017) MDR-TB cases were estimated to have occurred among previously treated TB cases alone. Three countries--China, India, and the Russian Federation--accounted for 261,362 (95% CI, 180,779-414,749) MDR-TB cases, or 62% of the estimated global burden.
  
  
  CONCLUSIONS
  These updated sets of estimates incorporating previously treated TB cases call for an urgent plan to expand appropriate diagnostic and treatment services for patients with MDR-TB in low-resource settings.
authors.affiliation: Stop TB Department, World Health Organization, Geneva 1211, Switzerland. zignolm@who.int
authors.forename: Matteo
authors.initials: M
authors.lastname: Zignol
authors.forename: Mehran S
authors.initials: MS
authors.lastname: Hosseini
authors.forename: Abigail
authors.initials: A
authors.lastname: Wright
authors.forename: Catharina Lambregts-van
authors.initials: CL
authors.lastname: Weezenbeek
authors.forename: Paul
authors.initials: P
authors.lastname: Nunn
authors.forename: Catherine J
authors.initials: CJ
authors.lastname: Watt
authors.forename: Brian G
authors.initials: BG
authors.lastname: Williams
authors.forename: Christopher
authors.initials: C
authors.lastname: Dye
mesh_terms: D014943:Global Health; D006285:Health Planning; D006801:Humans; D015994:Incidence; D016015:Logistic Models; D015233:Models, Statistical; D018088:Tuberculosis, Multidrug-Resistant / Q000453:epidemiology* / Q000382:microbiology / Q000517:prevention & control*