Q fever across the Dutch border in Limburg province, Belgium.

Data from three different data sources were compiled to estimate the presence of Coxiella burnetii in the Belgian Limburg province for both humans and livestock. First, serological data of all samples sent to the Belgian reference centre (2003–2010) for human Q fever were analysed, showing evidence for an acute Q fever infection in 1–5% of the cases. Second, a multi-centre prospective survey was conducted in Limburg in 2010 to detect undiagnosed human cases; evidence for a recent infection with Coxiella burnetii was found in three out of 100 patients from which clinicians suspected a Mycoplasma pneumoniae infection. Third, we analyzed data from the Belgian livestock screening program (2009–2010) which consisted of investigating all reported abortions, sampling tank milk, and serological screening of cattle. The results suggest an endemicity in the Limburgian livestock which seems to be especially high in cattle.