title: Epizootiological investigation of a Q fever outbreak and implications for future control strategies.
abstract: OBJECTIVE
  To describe the epizootiological investigation of an outbreak of Q fever (Coxiella burnetii infection).
  
  
  METHODS
  Epidemiological study.
  
  
  METHODS
  17 goat herds in Washington, Montana, and Oregon.
  
  
  METHODS
  In April 2011, an abortion storm at a commercial goat farm in Washington was determined to be caused by C burnetii. A joint epidemiological investigation by public health and veterinary professionals was subsequently performed to assess the extent of the outbreak by performing a trace-forward of goats sold from the index farm, to determine risk factors associated with infection, and to implement control measures. A herd management plan was developed to control the outbreak and reduce risk of human exposure. Quarantine and temporary holds preventing the sale or movement of goats allowed time for trace-forward investigation, education of farmers regarding disease risk, and testing to determine the scope of the outbreak.
  
  
  RESULTS
  17 farms were affected; 21 human Q fever cases were identified. Bacterial shedding in feces, vaginal fluid, or milk was confirmed in 156 of 629 (25%) goats tested by PCR assay. Seroprevalence of antibodies against C burnetii in goats, determined by ELISA, was 12%. The risk for C burnetii infection in goats was highest among females, those on farms associated with human Q fever, and those on Washington farms. A protective effect was observed for goats at farms where the primary form of goat carcass disposal was burial.
  
  
  CONCLUSIONS
  This outbreak illustrated the importance of a joint investigation for zoonotic pathogens and the need to expand and strengthen relationships between medical, public health, and veterinary partners. Heightened awareness and enhanced veterinary diagnostic capabilities for C burnetii are needed to identify and control outbreaks expediently.
authors.forename: Alicia D
authors.initials: AD
authors.lastname: Anderson
authors.forename: Tahnee J
authors.initials: TJ
authors.lastname: Szymanski
authors.forename: Michelle P
authors.initials: MP
authors.lastname: Emery
authors.forename: Paul H
authors.initials: PH
authors.lastname: Kohrs
authors.forename: Adam C
authors.initials: AC
authors.lastname: Bjork
authors.forename: Nicola
authors.initials: N
authors.lastname: Marsden-Haug
authors.forename: Randall J
authors.initials: RJ
authors.lastname: Nett
authors.forename: Dana M
authors.initials: DM
authors.lastname: Woodhall
authors.forename: Joshua S
authors.initials: JS
authors.lastname: Self
authors.forename: Kelly A
authors.initials: KA
authors.lastname: Fitzpatrick
authors.forename: Rachael A
authors.initials: RA
authors.lastname: Priestley
authors.forename: Gilbert J
authors.initials: GJ
authors.lastname: Kersh
mesh_terms: D000818:Animals; D001826:Body Fluids / Q000382:microbiology; D004196:Disease Outbreaks / Q000662:veterinary*; D005243:Feces / Q000382:microbiology; D005260:Female; D015511:Goat Diseases / Q000097:blood / Q000453:epidemiology / Q000382:microbiology* / Q000517:prevention & control; D006041:Goats; D006801:Humans; D008297:Male; D008892:Milk / Q000382:microbiology; D009009:Montana / Q000453:epidemiology; D009922:Oregon / Q000453:epidemiology; D016133:Polymerase Chain Reaction; D011778:Q Fever / Q000453:epidemiology / Q000662:veterinary*; D012698:Serologic Tests; D014621:Vagina / Q000382:microbiology; D014861:Washington / Q000453:epidemiology; D015047:Zoonoses