[Q-fever outbreak in Dortmund in the summer of 1999. Results of an epidemiological outbreak study].

In the summer of 1999, the health department of the City of Dortmund registered an increased incidence rate of reported Q-fever-diseases. Q-fever is a zoonosis caused by the Coxiella burnetii bacterium which typically multiplies within cells. To investigate the cause of this outbreak, an investigation was initiated. Clinical and veterinary examinations, investigations of the environment and an epidemiological case-control-study were combined. Patients as well as healthy persons interviewed for comparative purposes were asked to complete a questionnaire on their habits of life and the answers compared. The results of this study show a clear connection between an exposition with sheep, dung (OR = 14.9; 95% CI: 4.9-47) and manure (OR = 18.7; 95% CI: 3.5-180) of infected sheep and the Q-fever outbreak. The study confirmed the assumption that a local sheep farm was the source of infection for the epidemic outbreak of Q-fever in the same quarter of Dortmund.