Objective: Chronic infection is the major risk of Q fever. C. burnetii infections result from the inhalation of contaminated aerosols. Indre-et-Loire is a rural French area with numerous goat farms. We evaluated human Q fever epidemiology and compared it with Q fever in goats.
Design: This retrospective study was made between 2003 and 2005. The diagnosis of C. burnetii infection was based on serologic findings from all the subdivision laboratories. Antibodies were detected by using indirect immunofluorescence. Farm animal data was processed by ELISA on blood samples from goats and cattle after Q fever related abortion in 2006 and results of PCR-processed milk samples from 156 goat farms.
Results: Forty human cases were studied: 38 acute Q fever (11 pneumonia, 10 hepatitis, 10 pneumonia with hepatitis, two isolated fever) and six chronic Q fever (four endocarditis). Sixteen patients (40%) had been professionally exposed, 10 (25%) of whom were goat farmers. Eight (20%) had been in contact with placenta. All the human cases were located in the south of Indre-et-Loire. Twenty percent of the volunteer goat farms had at least one milk sample positive for Q fever by PCR. Forty-nine of the 75 goat abortion samples were positive in ELISA. Ninety-two of the goat farms with positive samples were located in the south of Indre-et-Loire.
Conclusion: This study revealed similar location of human and caprine Q fever. Identifying such geographical correlation may lead to improving prevention and detection.