title: Detection of Legionella by cultivation and quantitative real-time polymerase chain reaction in biological waste water treatment plants in Norway.
abstract: Cases of Legionnaires' disease associated with biological treatment plants (BTPs) have been reported in six countries between 1997 and 2010. However, knowledge about the occurrence of Legionella in BTPs is scarce. Hence, we undertook a qualitative and quantitative screening for Legionella in BTPs treating waste water from municipalities and industries in Norway, to assess the transmission potential of Legionella from these installations. Thirty-three plants from different industries were sampled four times within 1 year. By cultivation, 21 (16%) of 130 analyses were positive for Legionella species and 12 (9%) of 130 analyses were positive for Legionella pneumophila. By quantitative real-time polymerase chain reaction (PCR), 433 (99%) of 437 analyses were positive for Legionella species and 218 (46%) of 470 analyses were positive for L. pneumophila. This survey indicates that PCR could be the preferable method for detection of Legionella in samples from BTPs. Sequence types of L. pneumophila associated with outbreaks in Norway were not identified from the BTPs. We showed that a waste water treatment plant with an aeration basin can produce high concentrations of Legionella. Therefore, these plants should be considered as a possible source of community-acquired Legionella infections.
authors.affiliation: Division of Environmental Medicine, Department of Food, Water and Cosmetics, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway E-mail: vidar.lund@fhi.no.
authors.forename: Vidar
authors.initials: V
authors.lastname: Lund
authors.affiliation: Division of Environmental Medicine, Department of Food, Water and Cosmetics, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway E-mail: vidar.lund@fhi.no.
authors.forename: Wenche
authors.initials: W
authors.lastname: Fonahn
authors.affiliation: Division of Environmental Medicine, Department of Food, Water and Cosmetics, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway E-mail: vidar.lund@fhi.no.
authors.forename: Jens Erik
authors.initials: JE
authors.lastname: Pettersen
authors.affiliation: Division of Infectious Disease Control, Department of Bacteriology and Immunology, Norwegian Institute of Public Health, PO Box 4404 Nydalen, NO-0403 Oslo, Norway.
authors.forename: Dominique A
authors.initials: DA
authors.lastname: Caugant
authors.affiliation: Unilabs Laboratoriemedisin AS, Department of Environmental Microbiology, Leirvollen 19, 3736 Skien, Norway.
authors.forename: Eirik
authors.initials: E
authors.lastname: Ask
authors.affiliation: Unilabs Laboratoriemedisin AS, Department of Environmental Microbiology, Leirvollen 19, 3736 Skien, Norway.
authors.forename: Ase
authors.initials: A
authors.lastname: Nysaeter
mesh_terms: D015169:Colony Count, Microbial; D007875:Legionella / Q000235:genetics / Q000302:isolation & purification*; D009664:Norway; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D060888:Real-Time Polymerase Chain Reaction; D014865:Waste Disposal, Fluid; D062065:Wastewater / Q000382:microbiology*; D018508:Water Purification
chemical_list: D012336:RNA, Ribosomal, 16S; D062065:Wastewater