Coxiella burnetii in dairy goats with a history of reproductive disorders in Brazil

Coxiella burnetii, an intracellular bacterium, is the agent of Q fever/coxiellosis, a worldwide zoonosis. Dairy animals are the primary reservoirs of C. burnetii, and although the disease is usually asymptomatic or subclinical, abortion is a serious clinical outcome among small ruminants. This study was conducted to investigate C. burnetii seroprevalence and infection In a flock of dairy goats in Brazil. Serum samples from 312 goats collected from a dairy goat flock with a history of reproductive failure were tested by a commercial ELISA (LSIVet Ruminant Q Fever - Serum/Milk; Thermo Fisher Scientific, Lissieu, France) for anti-C. burnetii IgG antibodies. Samples of cotyledons from 23 placentas were analyzed by nested PCR for the presence of the bacterial DNA. ELISA seroreactivity was found in 55.1% (172/312; 95% CI = 49.4%-60.7%) of the serum samples analyzed. C. burnetii DNA was detected in 8.7% (2/23) of the placental samples tested, where both animals were also seropositive. This study reports the first description of C. burnetii infection in an abortion outbreak in goats in Brazil. The results point out to the importance of including this disease in animal and public health surveillance programs as well as into the list of abortive diseases in goats in Brazil.