title: Prevalence and diversity ofChlamydialesand other amoeba-resisting bacteria in domestic drinking water systems.
abstract: A growing number of human infections incriminate environmental bacteria that have evolved virulent mechanisms to resist amoebae and use them as a replicative niche. These bacteria are designated amoeba-resisting bacteria (ARB). Despite the isolation of these ARB in various human clinical samples, the possible source of infection remains undetermined in most cases. However, it is known that the ARBLegionella pneumophila,for instance, causes a respiratory infection in susceptible hosts after inhalation of contaminated water aerosols from various sources. TheChlamydialesorder contains many ARB, such asParachlamydia acanthamoebaeorSimkania negevensis,previously implicated in human respiratory infections with no identified contamination sources. We thus investigated whether domestic water systems are a potential source of transmission of theseChlamydialesto humans by using amoebal culture and molecular methods. Other important ARB such as mycobacteria andLegionellawere also investigated, as were their possible amoebal hosts. This work reports for the first time a very high prevalence and diversity ofChlamydialesin drinking water, being detected in 35 (72.9%) of 48 investigated domestic water systems, with members of theParachlamydiaceaefamily being dominantly detected. Furthermore, variousLegionellaand mycobacteria species were also recovered, some species of which are known to be causal agents of human infections.
authors.affiliation: Center for Research on Intracellular Bacteria, Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
authors.forename: J
authors.initials: J
authors.lastname: Lienard
authors.affiliation: Center for Research on Intracellular Bacteria, Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Croxatto
authors.affiliation: Children's Hospital of Geneva, University Hospitals of Geneva and Medical School of the University of Geneva, Geneva, Switzerland.
authors.forename: A
authors.initials: A
authors.lastname: Gervaix
authors.affiliation: University of Paris-Sud XI, Faculty of Pharmacy, Paris, France.
authors.forename: Y
authors.initials: Y
authors.lastname: Lévi
authors.affiliation: Suez Environnement CIRSEE, Le Pecq, France.
authors.forename: J-F
authors.initials: JF
authors.lastname: Loret
authors.affiliation: Children's Hospital of Geneva, University Hospitals of Geneva and Medical School of the University of Geneva, Geneva, Switzerland.
authors.forename: K M
authors.initials: KM
authors.lastname: Posfay-Barbe
authors.affiliation: Center for Research on Intracellular Bacteria, Institute of Microbiology, Lausanne University Hospital and University of Lausanne, Lausanne, Switzerland; Infectious Diseases Service, Lausanne University Hospital, Lausanne, Switzerland.
authors.forename: G
authors.initials: G
authors.lastname: Greub
keywords: Amoebal co-culture; Criblamydiaceae; Parachlamydiaceae; amoebal enrichment; biofilm