Q fever in Finland: clinical, immunological and epidemiological findings.

Clinical, immunological and epidemiological features of 14 human cases of Q fever diagnosed at Aurora Hospital are presented. All patients had an acute febrile disease and 9 (64%) had respiratory symptoms, 4 (29%) verified pneumonia, and 9 (64%) hepatitis, which in 4 biopsied cases proved to be granulomatous. Presence of circulating immune complexes was shown in 10/11 patients investigated by the platelet aggregation test (PAT) and the platelet iodinated protein A (PIPA) test. Q fever is not known to be endemic in the Nordic Countries. However, the causative agent, Coxiella burnetii, should tolerate our climate and there is a rich potential animal reservoir. All patients had visited some endemic area shortly before they were taken ill. In 3 cases the interval between arrival in Finland and the onset of symptoms was more than double the reported maximal incubation period, namely 69, 75 and 88 days. We suggest that these patients acquired the infection after their return to Finland from their clothing or from souvenirs. If so, Q fever could be acquired by this mechanism by persons who have never visited an area where the disease is endemic.