title: One-year follow-up of patients of the ongoing Dutch Q fever outbreak: clinical, serological and echocardiographic findings.
abstract: OBJECTIVE
  In 2007, a large goat-farming-associated Q fever outbreak occurred in the Netherlands. Data on the clinical outcome of Dutch Q fever patients are lacking. The current advocated follow-up strategy includes serological follow-up to detect evolution to chronic disease and cardiac screening at baseline to identify and prophylactically treat Q fever patients in case of valvulopathy. However, serological follow-up using commercially available tests is complicated by the lack of validated cut-off values. Furthermore, cardiac screening in the setting of a large outbreak has not been implemented previously. Therefore, we report here the clinical outcome, serological follow-up and cardiac screening data of the Q fever patients of the current ongoing outbreak.
  
  
  METHODS
  The implementation of a protocol including clinical and serological follow-up at baseline and 3, 6 and 12 months after acute Q fever and screening echocardiography at baseline.
  
  
  RESULTS
  Eighty-five patients with acute Q fever were identified (male 62%, female 38%). An aspecific, flu-like illness was the most common clinical presentation. Persistent symptoms after acute Q fever were reported by 59% of patients at 6 months and 30% at 12 months follow-up. We observed a typical serological response to Coxiella burnetii infection in both anti-phase I and anti-phase II IgG antibodies, with an increase in antibody titres up to 3 months and a subsequent decrease in the following 9 months. Screening echocardiography was available for 66 (78%) out of 85 Q fever patients. Cardiac valvulopathy was present in 39 (59%) patients. None of the 85 patients developed chronic Q fever.
  
  
  CONCLUSIONS
  Clinical, serological and echocardiographic data of the current ongoing Dutch Q fever outbreak cohort are presented. Screening echocardiography is no longer part of the standard work-up of Q fever patients in the Netherlands.
authors.affiliation: Department of Pulmonary Diseases, Canisius-Wilhelmina Hospital, Weg door Jonkerbos 100, 6525 SZ Nijmegen, The Netherlands. gjmlimonard@gmail.com
authors.forename: G J M
authors.initials: GJ
authors.lastname: Limonard
authors.forename: M H
authors.initials: MH
authors.lastname: Nabuurs-Franssen
authors.forename: G
authors.initials: G
authors.lastname: Weers-Pothoff
authors.forename: C
authors.initials: C
authors.lastname: Wijkmans
authors.forename: R
authors.initials: R
authors.lastname: Besselink
authors.forename: A M
authors.initials: AM
authors.lastname: Horrevorts
authors.forename: P M
authors.initials: PM
authors.lastname: Schneeberger
authors.forename: C A R
authors.initials: CA
authors.lastname: Groot
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015331:Cohort Studies; D016997:Coxiella burnetii / Q000502:physiology; D004196:Disease Outbreaks; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009426:Netherlands; D011778:Q Fever / Q000097:blood* / Q000000981:diagnostic imaging / Q000453:epidemiology / Q000473:pathology*; D012698:Serologic Tests; D014463:Ultrasonography