title: A case study of a dental receptionist diagnosed with Legionnaires' disease.
abstract: OBJECTIVE
  This article describes the search for the source of infection after a female dental receptionist was diagnosed with Legionnaires' disease.
  
  
  METHODS
  An environmental investigation was carried out to locate the source of the infection. Samples were taken from different sources at sites where the dental receptionist resided and worked, and tested for Legionella pneumophila. Thermal measures were employed to eliminate the favourable conditions for the growth of Legionellae.
  
  
  RESULTS
  The initial sampling of 13 sites indicated that there were four sample points which showed the presence of Legionella. Heat shock treatment of the hot water system was introduced as an intervention measure. A subsequent sampling of 14 sites indicated that two sample points showed the presence of Legionella. Water supply temperatures were found to be within the Legionella spp. ideal growth range. Faults were identified and measures were taken to regulate thermal temperatures outside the range which permits Legionellae growth.
  
  
  CONCLUSIONS
  There is scientific evidence that water used as a coolant and irrigant during dental procedures can be heavily contaminated with micro-organisms. Thermal control of water and measures to correct faulty water systems can assist in prevention of Legionnaires' disease.
authors.affiliation: Department of Interdisciplinary Health Sciences, Faculty of Health Sciences, Stellenbosch University, Tygerberg Campus, Parow, 7505, South Africa. umec@sun.ac.za
authors.forename: U M E
authors.initials: UM
authors.lastname: Chikte
authors.forename: O
authors.initials: O
authors.lastname: Khondowe
authors.forename: I
authors.initials: I
authors.lastname: Gildenhuys
mesh_terms: D000328:Adult; D058491:Bacterial Load; D003727:Dental Auxiliaries; D003770:Dental Offices; D004868:Equipment Failure; D005260:Female; D006268:Health Facilities; D006801:Humans; D007875:Legionella / Q000302:isolation & purification; D007877:Legionnaires' Disease / Q000175:diagnosis*; D009784:Occupational Diseases / Q000175:diagnosis*; D018410:Pneumonia, Bacterial / Q000175:diagnosis; D014871:Water Microbiology; D060753:Water Quality; D014881:Water Supply