title: Use of biomass fuel in households is not a risk factor for pulmonary tuberculosis in South Ethiopia.
abstract: METHODS
  Rural settings of Sidama Zone in southern Ethiopia.
  
  
  OBJECTIVE
  To investigate the association between exposure to biomass fuel smoke and tuberculosis (TB).
  
  
  METHODS
  A matched case control study in which cases were adult smear-positive pulmonary tuberculosis (PTB) patients on DOTS-based treatment at rural health institutions. Age-matched controls were recruited from the community.
  
  
  RESULTS
  Of 355 cases, 350 (98.6%) use biomass fuel for cooking, compared to 801/804 (99.6%) controls. PTB was not associated with exposure to the biomass fuel smoke. None of the factors such as heating the house, type of stove, presence of kitchen, presence of adequate cooking room ventilation, light source and number of rooms in the house was associated with the presence of TB. However, TB determinants such as sex, household contact with TB, history of TB treatment, smoking and presence of a smoker in the household have previously shown an association with TB.
  
  
  CONCLUSIONS
  We found no evidence of an association between the use of biomass fuel and TB. Low statistical power due to the selection of neighbourhood controls might have contributed to this negative finding. We would advise that future protocols should not use neighbourhood controls and that they should include measurements of indoor air pollution and of exposure duration.
authors.affiliation: Centre for International Health, University of Bergen, Bergen, Norway; and Department of Public and Environmental Health, Hawassa University, Hawassa, Ethiopia.
authors.forename: E M
authors.initials: EM
authors.lastname: Woldesemayat
authors.affiliation: Liverpool School of Tropical Medicine, Liverpool, UK; and TB Reach Project Ethiopia, Hawassa, Ethiopia.
authors.forename: D G
authors.initials: DG
authors.lastname: Datiko
authors.affiliation: Centre for International Health, University of Bergen, Bergen, Norway.
authors.forename: B
authors.initials: B
authors.lastname: Lindtjørn
mesh_terms: D000293:Adolescent; D000328:Adult; D016902:Air Pollution, Indoor / Q000009:adverse effects*; D000995:Antitubercular Agents / Q000627:therapeutic use; D018533:Biomass; D016022:Case-Control Studies; D003296:Cooking; D023801:Directly Observed Therapy; D005002:Ethiopia; D005260:Female; D005579:Fossil Fuels / Q000009:adverse effects*; D006798:Housing; D006801:Humans; D019570:Inhalation Exposure / Q000009:adverse effects; D008297:Male; D008875:Middle Aged; D012307:Risk Factors; D012423:Rural Health; D013997:Time Factors; D014397:Tuberculosis, Pulmonary / Q000175:diagnosis / Q000188:drug therapy / Q000209:etiology*; D055815:Young Adult
chemical_list: D000995:Antitubercular Agents; D005579:Fossil Fuels