Rethinking Coxiella infections in Australia

Abstract

Coxiellaburnetii is the causative agent of coxiellosis in animals and Q fever in humans. Despite being a vaccine preventable disease, Q fever remains a frequently reported zoonotic infection in Australia. Recently, a Coxiella species was identified in brown dog ticks (Rhipicephalus sanguineus) in urban and rural regions of Australia. Further molecular characterisation revealed that it is genetically identical to ‘Candidatus Coxiella massiliensis’ (KM079627) described in R. sanguineus ticks removed from humans with eschars in France and serologic cross-reactivity among ‘Ca. Coxiella massiliensis’ and C.burnetii may occur. This report highlights the need for molecular testing of seropositive companion animals and humans to determine which species of Coxiella they are infected with, in order to further assess Coxiella species associated with Coxiella infections in Australia.