title: High prevalence of tuberculosis and insufficient case detection in two communities in the Western Cape, South Africa.
abstract: BACKGROUND
  In South Africa the estimated incidence of all forms of tuberculosis (TB) for 2008 was 960/100000. It was reported that all South Africans lived in districts with Directly Observed Therapy, Short-course. However, the 2011 WHO report indicated South Africa as the only country in the world where the TB incidence is still rising.
  
  
  OBJECTIVE
  To report the results of a TB prevalence survey and to determine the speed of TB case detection in the study communities.
  
  
  METHODS
  In 2005 a TB prevalence survey was done to inform the sample size calculation for the ZAMSTAR (Zambia South Africa TB and AIDS Reduction) trial. It was a cluster survey with clustering by enumeration area; all households were visited within enumeration areas and informed consent obtained from eligible adults. A questionnaire was completed and a sputum sample collected from each adult. Samples were inoculated on both liquid mycobacterium growth indicator tube (MGIT) and Löwenstein-Jensen media. A follow-up HIV prevalence survey was done in 2007.
  
  
  RESULTS
  In Community A, the adjusted prevalence of culture positive TB was 32/1000 (95%CI 25-41/1000) and of smear positive TB 8/1000 (95%CI 5-13/1000). In Community B, the adjusted prevalence of culture positive TB was 24/1000 (95%CI 17-32/1000) and of smear positive TB 9/1000 (95%CI 6-15/1000). In Community A the patient diagnostic rate was 0.38/person-year while in community B it was 0.30/person-year. In both communities the adjusted HIV prevalence was 25% (19-30%).
  
  
  CONCLUSIONS
  In both communities a higher TB prevalence than national estimates and a low patient diagnostic rate was calculated, suggesting that cases are not detected at a sufficient rate to interrupt transmission. These findings may contribute to the rising TB incidence in South Africa. The TB epidemic should therefore be addressed rapidly and effectively, especially in the presence of the concurrently high HIV prevalence.
authors.affiliation: Desmond Tutu Tuberculosis Centre, Department of Paediatrics and Child Health, Stellenbosch University, Tygerberg, South Africa. mcla@sun.ac.za
authors.forename: Mareli
authors.initials: M
authors.lastname: Claassens
authors.forename: Cari
authors.initials: C
authors.lastname: van Schalkwyk
authors.forename: Leonie
authors.initials: L
authors.lastname: den Haan
authors.forename: Sian
authors.initials: S
authors.lastname: Floyd
authors.forename: Rory
authors.initials: R
authors.lastname: Dunbar
authors.forename: Paul
authors.initials: P
authors.lastname: van Helden
authors.forename: Peter
authors.initials: P
authors.lastname: Godfrey-Faussett
authors.forename: Helen
authors.initials: H
authors.lastname: Ayles
authors.forename: Martien
authors.initials: M
authors.lastname: Borgdorff
authors.forename: Donald
authors.initials: D
authors.lastname: Enarson
authors.forename: Nulda
authors.initials: N
authors.lastname: Beyers
mesh_terms: D000293:Adolescent; D000328:Adult; D000995:Antitubercular Agents / Q000627:therapeutic use; D015897:Comorbidity; D023801:Directly Observed Therapy; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000453:epidemiology*; D006306:Health Surveys; D006801:Humans; D007538:Isoniazid / Q000627:therapeutic use; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D012293:Rifampin / Q000627:therapeutic use; D012463:Saliva / Q000821:virology; D013019:South Africa / Q000453:epidemiology; D013183:Sputum / Q000382:microbiology; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology*; D015024:Zambia / Q000453:epidemiology
chemical_list: D000995:Antitubercular Agents; D007538:Isoniazid; D012293:Rifampin
references.citation: Epidemiol Rev. 2001;23(2):288-301
references.pmid: 12192738
references.citation: PLoS Med. 2007 Jan;4(1):e22
references.pmid: 17199408
references.citation: Am J Respir Crit Care Med. 2007 Jan 1;175(1):87-93
references.pmid: 16973982
references.citation: Emerg Infect Dis. 2004 Sep;10(9):1523-8
references.pmid: 15498151
references.citation: Lancet. 2010 May 22;375(9728):1814-29
references.pmid: 20488524
references.citation: Lancet. 1998 Dec 12;352(9144):1886-91
references.pmid: 9863786
references.citation: PLoS One. 2009;4(5):e5602
references.pmid: 19440346
references.citation: Int J Tuberc Lung Dis. 2008 Oct;12(10):1110-5
references.pmid: 18812038
references.citation: Trials. 2008 Nov 07;9:63
references.pmid: 18992133
references.citation: Emerg Infect Dis. 2007 Aug;13(8):1189-94
references.pmid: 17953090
references.citation: S Afr Med J. 2006 Jun;96(6):538-43
references.pmid: 16841139