Coxiella burnetii, the etiological agent of Q-fever has recently been isolated from sheep in southern Sweden. In this region 24-30% of sheep farmers have been exposed to the organism as shown by serological measurements. In veterinarians, another group with high risk of exposure to C. burnetii, about 12% have antibodies to the bacteria. The seropositive veterinarians are scattered all over the country. In two non-risk groups, draftees and hospital employees, 5-7% were found to be positive. This survey showed that Q-fever is a domestic disease which is spread throughout Sweden.

Coxiella burnetii was isolated from sheep placentas, which had been collected from farms harbouring humans seropositive to the organism. The isolation of these bacteria is the final evidence that Q fever is a domestic disease in Sweden.

Q fever is known to be a worldwide disease, with Sweden supposed to be one of a few exceptions. The purpose of this pilot study was to elucidate whether or not a potential risk group for obtaining Q fever in Sweden was seropositive to the causative agent Coxiella burnetii. Blood samples were collected from sheep farmers on the island of Gotland, and from members of their families. Serum samples were examined by ELISA for the presence of antibodies against C. burnetii, phases I and II. Positive reactions were confirmed with Western blot analysis. It was found that 30% of the study group were seropositive to C. burnetii, thus indicating that Q fever is endemic in this area of Sweden.