title: Pilot study to detect airborne Mycobacterium tuberculosis exposure in a South African public healthcare facility outpatient clinic.
abstract: BACKGROUND
  Airborne transmission of Mycobacterium tuberculosis remains an occupational health hazard, particularly in crowded and resource-limited healthcare settings.
  
  
  OBJECTIVE
  To quantify airborne M. tuberculosis in a busy outpatient clinic in Gauteng, South Africa.
  
  
  METHODS
  Stationary air samples and samples from healthcare workers (HCWs) were collected in the polyclinic and administrative block. Quantitative real-time polymerase chain reaction (PCR) was used to detect airborne M. tuberculosis. Walkthrough observations and work practices of HCWs were also recorded.
  
  
  RESULTS
  In total, M. tuberculosis was detected in 11 of 49 (22.4%) samples: nine of 25 (36%) HCW samples and two of 24 (8.3%) stationary air samples. Samples from five of 10 medical officers (50%) and three of 13 nurses (23%) were positive. Repeat measurements on different days showed variable results. Most of the HCWs (87.5%) with positive results had been in contact with coughing patients and had not worn respiratory masks despite training.
  
  
  CONCLUSIONS
  The use of air sampling coupled with quantitative real-time PCR is a simple and effective tool to demonstrate the risk of M. tuberculosis exposure. The findings provide an impetus for hospital management to strengthen infection prevention and control measures for tuberculosis.
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa; Department of Clinical Microbiology and Infectious Diseases, School of Pathology, University of Witwatersrand, Johannesburg, South Africa.
authors.forename: O
authors.initials: O
authors.lastname: Matuka
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa; Department of Clinical Microbiology and Infectious Diseases, School of Pathology, University of Witwatersrand, Johannesburg, South Africa. Electronic address: Tanusha.singh@nioh.nhls.ac.za.
authors.forename: T S
authors.initials: TS
authors.lastname: Singh
authors.affiliation: Department of Pathology and Laboratory Medicine, University of British Columbia, Vancouver, BC, Canada.
authors.forename: E
authors.initials: E
authors.lastname: Bryce
authors.affiliation: School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada.
authors.forename: A
authors.initials: A
authors.lastname: Yassi
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa.
authors.forename: O
authors.initials: O
authors.lastname: Kgasha
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa; Department of Public Health Medicine, School of Health Systems and Public Health, University of Pretoria, Pretoria, South Africa.
authors.forename: M
authors.initials: M
authors.lastname: Zungu
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa.
authors.forename: K
authors.initials: K
authors.lastname: Kyaw
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa.
authors.forename: M
authors.initials: M
authors.lastname: Malotle
authors.affiliation: National Institute for Occupational Health, National Health Laboratory Service, Johannesburg, South Africa.
authors.forename: K
authors.initials: K
authors.lastname: Renton
authors.affiliation: School of Population and Public Health, University of British Columbia, Vancouver, BC, Canada.
authors.forename: L
authors.initials: L
authors.lastname: O'Hara
mesh_terms: D000328:Adult; D000391:Air Microbiology; D016902:Air Pollution, Indoor / Q000032:analysis; D000554:Ambulatory Care Facilities / Q000592:standards; D003428:Cross Infection / Q000382:microbiology / Q000517:prevention & control; D004269:DNA, Bacterial / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods; D005260:Female; D006282:Health Personnel; D006801:Humans; D017758:Infectious Disease Transmission, Patient-to-Professional; D008297:Male; D009169:Mycobacterium tuberculosis / Q000302:isolation & purification*; D016273:Occupational Exposure / Q000032:analysis*; D010865:Pilot Projects; D060888:Real-Time Polymerase Chain Reaction / Q000379:methods; D013019:South Africa; D014376:Tuberculosis / Q000382:microbiology / Q000517:prevention & control / Q000635:transmission
chemical_list: D004269:DNA, Bacterial
keywords: Air sampling; Healthcare workers; Infection prevention and control; Occupational exposure; Polymerase chain reaction; Tuberculosis