Coxiella burnetii Shedding by Farmed Red Deer (Cervus elaphus)

Wildlife and notably deer species--due to the increasing relevance of deer farming worldwide--may contribute to the maintenance of Coxiella burnetii, the causal agent of Q fever. Currently, there are no precedents linking exposure to deer species with human Q fever cases. However, a human case of Q fever was recently diagnosed in a red deer (Cervus elaphus) farm, which led us to investigate whether deer could be a source for environmental contamination with C. burnetii and ascertain the implication of C. burnetii in reproductive failure in the farm. Blood serum and vaginal swabs were collected from hinds either experiencing or not reproductive failure and tested to detect the presence of antibodies and DNA, respectively, of C. burnetii, Chlamydia abortus, Neospora caninum and Toxoplasma gondii. Serology and PCR results suggest C. burnetii was the primary cause of the reproductive failure. We identified vaginal shedding of C. burnetii in hinds, confirming red deer as a source of Q fever zoonotic infection.