a1 Centre for Infectious Disease Control, National Institute for Public Health and the Environment, RIVM, Bilthoven, The Netherlands
a2 European Programme for Intervention Epidemiology Training (EPIET), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
a3 Municipal Health Service Brabant-Zuidoost, Eindhoven, The Netherlands
Between February and May 2009, 347 laboratory-confirmed cases of acute Q fever were reported in a southern municipal health service region in The Netherlands. Commercial dairy-goat farms were implicated and control measures were initially targeted there. A preliminary investigation also implicated a non-dairy sheep farm, open to the public on ‘lamb-viewing days’. This study tested the association between visiting the non-dairy sheep farm and developing Q fever in residents of the region between February and May 2009. A case-control study of 146 cases and 431 address-matched controls was conducted. Multivariable logistic regression analysis confirmed the association between visiting to the sheep farm and Q fever disease (matched odds ratio 43, 95% confidence interval 9–200). Other risk factors were being a smoker, having a past medical history and being aged >40 years. Vaccination of sheep and goats on farms open to the public should help to reduce the number of future human cases.
(Accepted July 05 2011)
(Online publication August 11 2011)
c1 Author for correspondence: Dr J. Whelan, P.218 Postbak 75, Epidemiology & Surveillance Unit (EPI), National Institute for Public Health and the Environment (RIVM), PO Box 1, 3720 BA Bilthoven, The Netherlands. (Email: firstname.lastname@example.org)