title: Genetic diversity of human pathogenic members of the Fusarium oxysporum complex inferred from multilocus DNA sequence data and amplified fragment length polymorphism analyses: evidence for the recent dispersion of a geographically widespread clonal lineage and nosocomial origin.
abstract: Fusarium oxysporum is a phylogenetically diverse monophyletic complex of filamentous ascomycetous fungi that are responsible for localized and disseminated life-threatening opportunistic infections in immunocompetent and severely neutropenic patients, respectively. Although members of this complex were isolated from patients during a pseudoepidemic in San Antonio, Tex., and from patients and the water system in a Houston, Tex., hospital during the 1990s, little is known about their genetic relatedness and population structure. This study was conducted to investigate the global genetic diversity and population biology of a comprehensive set of clinically important members of the F. oxysporum complex, focusing on the 33 isolates from patients at the San Antonio hospital and on strains isolated in the United States from the water systems of geographically distant hospitals in Texas, Maryland, and Washington, which were suspected as reservoirs of nosocomial fusariosis. In all, 18 environmental isolates and 88 isolates from patients spanning four continents were genotyped. The major finding of this study, based on concordant results from phylogenetic analyses of multilocus DNA sequence data and amplified fragment length polymorphisms, is that a recently dispersed, geographically widespread clonal lineage is responsible for over 70% of all clinical isolates investigated, including all of those associated with the pseudoepidemic in San Antonio. Moreover, strains of the clonal lineage recovered from patients were conclusively shown to genetically match those isolated from the hospital water systems of three U.S. hospitals, providing support for the hypothesis that hospitals may serve as a reservoir for nosocomial fusarial infections.
authors.affiliation: National Center for Agricultural Utilization Research, U.S. Department of Agriculture, Peoria, IL 61604-3999, USA. kodonnell@mail.ncaur.usda.gov
authors.forename: Kerry
authors.initials: K
authors.lastname: O'Donnell
authors.forename: Deanna A
authors.initials: DA
authors.lastname: Sutton
authors.forename: Michael G
authors.initials: MG
authors.lastname: Rinaldi
authors.forename: Karen C
authors.initials: KC
authors.lastname: Magnon
authors.forename: Patricia A
authors.initials: PA
authors.lastname: Cox
authors.forename: Sanjay G
authors.initials: SG
authors.lastname: Revankar
authors.forename: Stephen
authors.initials: S
authors.lastname: Sanche
authors.forename: David M
authors.initials: DM
authors.lastname: Geiser
authors.forename: Jean H
authors.initials: JH
authors.lastname: Juba
authors.forename: Jo-Anne H
authors.initials: JA
authors.lastname: van Burik
authors.forename: Arvind
authors.initials: A
authors.lastname: Padhye
authors.forename: Elias J
authors.initials: EJ
authors.lastname: Anaissie
authors.forename: Andrea
authors.initials: A
authors.lastname: Francesconi
authors.forename: Thomas J
authors.initials: TJ
authors.lastname: Walsh
authors.forename: Jody S
authors.initials: JS
authors.lastname: Robinson
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics; D003428:Cross Infection / Q000453:epidemiology* / Q000382:microbiology; D004783:Environmental Microbiology; D005670:Fusarium / Q000145:classification* / Q000235:genetics* / Q000472:pathogenicity; D014644:Genetic Variation; D014943:Global Health; D006761:Hospitals; D006801:Humans; D008396:Maryland; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D009181:Mycoses / Q000453:epidemiology* / Q000382:microbiology; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D017422:Sequence Analysis, DNA; D013781:Texas; D014861:Washington; D014881:Water Supply
chemical_list: D001426:Bacterial Proteins