title: Genetic typing in a cluster of Legionella pneumophila infections.
abstract: Legionella pneumophila strains isolated from six patients, three air-conditioning- and cooling tower-derived strains, and three hot water supply-derived strains were analyzed by three genetic typing methods. The results of the whole-cell DNA restriction endonuclease analysis and the restriction patterns based on genes coding for rRNA correlated with each other and demonstrated that the patient isolates were indistinguishable from the air-conditioning- and cooling tower-derived isolates but differed markedly from the hot water supply-derived isolates. The patient and air-conditioning- and cooling tower-derived strains contained plasmids of the same molecular weight; the hot water supply-derived strains were plasmidless. These results indicated that the cooling tower or the air-conditioning system was the environmental source for the examined cluster of Legionnaires disease strains.
authors.affiliation: Department of Medical Microbiology, University of Amsterdam, The Netherlands.
authors.forename: R J
authors.initials: RJ
authors.lastname: van Ketel
authors.forename: B
authors.initials: B
authors.lastname: de Wever
mesh_terms: D000389:Air Conditioning; D001345:Autoradiography; D003428:Cross Infection / Q000382:microbiology*; D004269:DNA, Bacterial / Q000032:analysis; D005838:Genotype; D006358:Hot Temperature; D006801:Humans; D007875:Legionella / Q000145:classification* / Q000235:genetics; D007877:Legionnaires' Disease / Q000382:microbiology*; D009426:Netherlands; D009693:Nucleic Acid Hybridization; D010957:Plasmids; D012335:RNA, Ribosomal / Q000235:genetics; D015183:Restriction Mapping; D014871:Water Microbiology; D014881:Water Supply
chemical_list: D004269:DNA, Bacterial; D012335:RNA, Ribosomal