title: Isolation of Coxiella burnetii from serum of patients with acute Q fever.
abstract: Worldwide there are few isolate collections of the intracellular bacterium Coxiella burnetii, due to the difficulties associated with working with the organism and the scarcity of suitable samples from which to attempt isolation. Particularly lacking are isolates from acute Q fever patients. The aim of this study was to evaluate whether the serum samples taken from patients with confirmed acute Q fever during the early stage of their disease represented a potential source of viable C. burnetii. Isolation was attempted from 65 of these samples by inoculation of the serum into Vero cell culture and was successful in 36 cases (55%). This high success rate was likely due to extended incubation of up to twelve weeks of the inoculated cultures, allowing the growth of the organism to levels detectable by PCR. Retrospective analysis of the time the sera was stored prior to inoculation into culture demonstrated that C. burnetii remained viable for 224 days in samples stored refrigerated and 371 days in samples stored frozen at -20 °C. These results demonstrate that standard serum samples taken from acute Q fever patients are a valuable source of new isolates of C. burnetii, with no special handling of the specimens required to maintain the organism's viability.
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia. Electronic address: gvince@barwonhealth.org.au.
authors.forename: Gemma A
authors.initials: GA
authors.lastname: Vincent
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Pathology North-Hunter, NSW Health Pathology, Locked Bag 1, Hunter Region Mail Centre, New South Wales 2310, Australia.
authors.forename: Stephen R
authors.initials: SR
authors.lastname: Graves
authors.affiliation: Sullivan Nicolaides Pathology, Whitmore Street, Taringa, Queensland 4068, Australia.
authors.forename: Jennifer M
authors.initials: JM
authors.lastname: Robson
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia.
authors.forename: Chelsea
authors.initials: C
authors.lastname: Nguyen
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia.
authors.forename: Hazizul
authors.initials: H
authors.lastname: Hussain-Yusuf
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Pathology North-Hunter, NSW Health Pathology, Locked Bag 1, Hunter Region Mail Centre, New South Wales 2310, Australia.
authors.forename: Aminul
authors.initials: A
authors.lastname: Islam
authors.affiliation: Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia; DAI, 93/1 GPF Witthayu Tower B, 12th Floor, Wireless Road, Lumpini, Pathamwan, Bangkok 10330, Thailand.
authors.forename: Stanley G
authors.initials: SG
authors.lastname: Fenwick
authors.affiliation: Australian Rickettsial Reference Laboratory, Barwon Health, University Hospital Geelong, PO Box 281, Geelong, Victoria 3220, Australia; Murdoch University, 90 South Street, Murdoch, Western Australia 6150, Australia.
authors.forename: John
authors.initials: J
authors.lastname: Stenos
mesh_terms: D000818:Animals; D002522:Chlorocebus aethiops; D016997:Coxiella burnetii / Q000235:genetics / Q000254:growth & development / Q000302:isolation & purification*; D006801:Humans; D011778:Q Fever / Q000097:blood / Q000175:diagnosis / Q000382:microbiology*; D012189:Retrospective Studies; D044967:Serum / Q000382:microbiology*; D014709:Vero Cells
keywords: Cell culture; Coxiella burnetii; Isolation; Q fever