A pedagogical farm as a source of Q fever in a French city.

Q fever is a worldwide zoonosis caused by Coxiella burnetii and presents as both acute or chronic cases. The disease can be transmitted from animal reservoirs to humans by inhalation of infected aerosols. A previous study had revealed a hyperendemic focus in South France. A case-control study was carried-out in this area from 1996 to 1999. Besides the role of wind, this study stressed out the exposure to a pedagogical farm as an independent risk factor (4.7% of cases - 0 controls): Exposure to sheep and new-born animals (OR: 3.07 and 4.01 respectively) were not significant after omission of people exposed to the pedagogical farm. Such farms are visited by people who would not have any other contact with farm animals. These farms require a drastic hygiene and control. Q fever, as a public health problem, still requires further studies to identify and confirm individual behavioral risk factors.

Wind in November, Q fever in December.

Q fever, a worldwide zoonosis caused by Coxiella burnetii, can be transmitted from animal reservoirs to humans by the inhalation of infected aerosols. We investigated the epidemiology of Q fever in the Bouches-du-Rhone district of southern France, particularly the role of wind and rainfall in C. burnetii transmission. During the winter of 1998 to 1999, an unexpected number of cases were diagnosed in the area. This statistically higher incidence was associated with an increased frequency of the mistral 1 month before onset of disease, i.e., shortly after the main lambing season. These data confirm that wind plays a role in C. burnetii transmission, a factor that can be monitored but not prevented. Further studies are needed to identify and confirm preventable individual behavioral risk factors for Q fever.