Q fever: still more queries than answers.

Q fever is a worldwide zoonosis, caused by C. burnetii. Infection usually occurs through inhalation of infected aerosols. The reservoir mainly consists of dairy cattle. Clinical symptoms of acute Q fever are non-specific and resemble a mild flu-like illness. Children often present with gastrointestinal symptoms and rash. Rarely, chronic infection develops. This is usually manifested as endo-carditis, vascular infection and, in children, osteomyelitis. Diagnosis is based on serology and nucleic acid amplification (PCR). Doxycycline is the treatment of choice for acute infection. An alternative for young children and pregnant women is cotrimoxazole. Chronic infection requires long term treatment usually with doxycycline combined with hydroxychloroquine.