Pseudoepidemic of Q fever at an animal research facility.
Serum samples from people exposed to sheep at a research facility were evaluated by a commercial laboratory and resulted in an overall Coxiella burnetii seroprevalence of 75%. We interviewed individuals to determine exposure history and compatible illness, and retested their sera. Analysis indicated that the commercial laboratory was misinterpreting its results; when corrected, the seroprevalence dropped to 27%. Test kits of the brand used by the commercial laboratory gave equivalent results to the in-house CDC assay when tested in parallel at CDC. Upon final analysis, only the attending veterinarian was confirmed as a Q fever case. This event resulted in increased risk reduction protocols at the research facility and improved public health communication among health authorities. This pseudoepidemic resulted from a lapse in laboratory quality control for testing. Similar errors can be avoided through standardization and improved review of laboratory procedures.
Conti
Lisa A
LA
Florida Department of Health, Tallahassee, Florida, USA. lisa_conti@doh.state.fl.us
Belcuore
Thomas R
TR
Nicholson
William L
WL
Paddock
Christopher D
CD
Jenelle
Jennifer
J
Singleton
Joseph
J
Childs
James E
JE
Huey
Michael
M
Wiersma
Steven
S
Hopkins
Richard S
RS
D000818:Animals; D000907:Antibodies, Bacterial / Q000097:blood; D002487:Centers for Disease Control and Prevention, U.S.; D019411:Clinical Laboratory Techniques / Q000592:standards*; D016997:Coxiella burnetii / Q000276:immunology; D004196:Disease Outbreaks; D004797:Enzyme-Linked Immunosorbent Assay; D005431:Florida / Q000453:epidemiology; D006801:Humans; D007753:Laboratories / Q000592:standards*; D011778:Q Fever / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D011786:Quality Control; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D016036:Seroepidemiologic Studies; D012756:Sheep; D012757:Sheep Diseases / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D014481:United States
D000907:Antibodies, Bacterial