Coxiella burnetii seroprevalence in primiparous and multiparous ewes from southern Australia: a cross-sectional study

Coxiella burnetii can cause reproductive disease in sheep and zoonotic Q-fever infections in humans. The role of infectious diseases including coxiellosis in causing poorer reproductive performance of primiparous ewes is not well studied. The aim of this study was to determine if natural exposure to C. burnetii is associated with poor reproductive performance of primiparous ewes and compare seroprevalence of primiparous and multiparous ewes. Coxiella burnetii seroprevalence was 0.08% (95% confidence interval 0.01, 0.36) in primiparous ewes and 0.36% (0.07, 1.14) in mature ewes. Coxiella burnetii was not detected in tissue samples from aborted or stillborn lambs using molecular diagnostic tests (qPCR). These findings suggest that C. burnetii infection was unlikely to be an important contributor to abortion and perinatal mortalities observed for primiparous ewes, and exposure to C. burnetii was not widespread in ewes on farms located over wide geographical region of southern Australia.