title: Tuberculosis burden in an urban population: a cross sectional tuberculosis survey from Guinea Bissau.
abstract: BACKGROUND
  Little is known about the prevalence of pulmonary tuberculosis (TB) in low income countries. We conducted a cross sectional survey for pulmonary TB and TB symptoms in Bissau, Guinea-Bissau, in an urban cohort with known HIV prevalence. TB surveillance in the area is routinely based on passive case finding.
  
  
  METHODS
  Two cohorts were selected based on a previous HIV survey, but only 52.5% of those enrolled in the adult cohort had participated in the HIV survey. One cohort included all adults living in 384 randomly selected houses; in this cohort 8% (135/1687) were HIV infected. The other included individuals 50 years or older from all other houses in the study area; of these 11% (62/571) were HIV infected. Symptom screening was done through household visits using a standardised questionnaire. TB suspects were investigated with sputum smear microscopy and X-ray.
  
  
  RESULTS
  In the adult cohort, we found 4 cases among 2989 individuals screened, giving a total TB prevalence of 134/100,000 (95% CI 36-342/100,000). In the >50 years cohort, we found 4 cases among 571 individuals screened, giving a total prevalence of 701/100,000 (191-1784/100.000). Two of the eight detected TB cases were unknown by the TB program. Of the total TB cases five were HIV uninfected while three had unknown HIV status. The prevalence of TB symptoms was 2.1% (63/2989) and 10.3% (59/571) in the two cohorts respectively.
  
  
  CONCLUSIONS
  In conclusion we found a moderately high prevalence of pulmonary TB and TB symptoms in the general population, higher among elderly individuals. By active case finding unknown cases were detected. Better awareness of TB and its symptoms needs to be promoted in low income settings.
authors.affiliation: Bandim Health Project, INDEPTH Network, Apartado 861, 1004 Bissau Codex, Guinea-Bissau. mban@dadlnet.dk
authors.forename: Morten
authors.initials: M
authors.lastname: Bjerregaard-Andersen
authors.forename: Zacarias J
authors.initials: ZJ
authors.lastname: da Silva
authors.forename: Pernille
authors.initials: P
authors.lastname: Ravn
authors.forename: Morten
authors.initials: M
authors.lastname: Ruhwald
authors.forename: Paul L
authors.initials: PL
authors.lastname: Andersen
authors.forename: Morten
authors.initials: M
authors.lastname: Sodemann
authors.forename: Per
authors.initials: P
authors.lastname: Gustafson
authors.forename: Peter
authors.initials: P
authors.lastname: Aaby
authors.forename: Christian
authors.initials: C
authors.lastname: Wejse
mesh_terms: D000818:Animals; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D006169:Guinea-Bissau / Q000453:epidemiology; D015658:HIV Infections / Q000150:complications / Q000453:epidemiology; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification; D015995:Prevalence; D013902:Radiography, Thoracic; D013183:Sputum / Q000382:microbiology; D011795:Surveys and Questionnaires; D014376:Tuberculosis / Q000453:epidemiology* / Q000473:pathology; D014505:Urban Population
references.citation: Trop Med Int Health. 2007 Apr;12(4):475-84
references.pmid: 17445138
references.citation: Lancet. 2006 Mar 18;367(9514):938-40
references.pmid: 16546542
references.citation: Am J Respir Crit Care Med. 2007 Jan 1;175(1):87-93
references.pmid: 16973982
references.citation: Bull World Health Organ. 2007 Aug;85(8):593-9
references.pmid: 17768517
references.citation: AIDS. 2008 Jun 19;22(10):1195-202
references.pmid: 18525265
references.citation: JAMA. 2001 Aug 1;286(5):599-603
references.pmid: 11476664
references.citation: BMC Public Health. 2008 Jan 14;8:15
references.pmid: 18194573
references.citation: PLoS Med. 2007 Jan;4(1):e22
references.pmid: 17199408
references.citation: Int J Epidemiol. 2003 Oct;32(5):744-52
references.pmid: 14559743
references.citation: Int J Tuberc Lung Dis. 2003 Dec;7(12):1154-62
references.pmid: 14677890
references.citation: Am J Respir Crit Care Med. 2004 Sep 15;170(6):673-9
references.pmid: 15191919
references.citation: Lancet Infect Dis. 2008 Apr;8(4):233-43
references.pmid: 18201929
references.citation: Lancet. 2007 Jun 16;369(9578):2042-2049
references.pmid: 17574096
references.citation: Epidemiol Infect. 2006 Oct;134(5):1052-9
references.pmid: 16569271
references.citation: Int J Epidemiol. 2004 Feb;33(1):163-72
references.pmid: 15075165
references.citation: Int J Tuberc Lung Dis. 2001 Mar;5(3):240-9
references.pmid: 11326823
references.citation: Int J Tuberc Lung Dis. 2006 Feb;10(2):184-7
references.pmid: 16499258
references.citation: JAMA. 2005 Jun 8;293(22):2767-75
references.pmid: 15941807
references.citation: Lancet. 2004 Jul 31-Aug 6;364(9432):417-22
references.pmid: 15288739
references.citation: Int J Tuberc Lung Dis. 1999 Jun;3(6):471-7
references.pmid: 10383058
references.citation: Int J Tuberc Lung Dis. 2006 Jan;10(1):87-92
references.pmid: 16466043
references.citation: Int J Tuberc Lung Dis. 2007 Apr;11(4):398-404
references.pmid: 17394685