Coxiella burnetii seropositivity and associated risk factors in goats in Ontario, Canada

A mixed multivariable logistic model that controlled for farm-level clustering identified risk factors associated with seropositivity (p < 0.05). Increases in the female herd size (logarithmic scale) were associated with increased odds of seropositivity, while increases in male herd size had a negative association with seropositivity. If other sheep or goat farms were located in a 5-km radius, goats had 5.6 times (95% CI = 1.01-30.8) times the odds of seropositivity compared to those that were not. Relative to goats from farms where all kidding pen hygiene was practiced (adding bedding, removing birth materials and disinfection after kidding), goats from farms which only added bedding and removed birth materials had a higher odds of seropositivity (OR = 19.3, 95% CI = 1.1-330.4), as did goats from farms which practiced none of these measures (OR = 161.0, 95% CI = 2.4-10822.2). An interaction term revealed kidding outdoors when there were no swine on farm had a protective effect on seropositivity compared to kidding indoors, or kidding outdoors with swine on the farm. These results can inform strategies to mitigate exposure to C. burnetii in Ontario.