Endemic Q Fever in New South Wales, Australia: A case series (2005-2013)

Abstract

Q fever is endemic in Australia, and during the period 2005-2013 our laboratory diagnosed 379 cases in New South Wales. To evaluate clinical symptoms, epidemiology, mode of diagnosis, antibody profiles, and treatment, a subset of 160 (42%) Q fever cases were analyzed in detail following the return of a questionnaire by the patient's doctor and from their laboratory reports. Overall, 82% patients were male and predominantly middle aged. The majority of patients (89%) had animal contact among which 63% were with cattle, 11% with sheep, and 7% with kangaroos. Clinical symptoms were nonspecific: myalgia (94%), fever (91%), headache (80%), acute fatigue (64%), and arthralgia (55%). Most cases (93%) were acute, and serology (immunofluorescence) was the main diagnostic modality. Positive real-time polymerase chain reaction results were useful in the diagnosis of both acute and chronic Q fever, as was the isolation of Coxiella burnetii in cell culture. Doxycycline was the antibiotic most commonly used.