Antimicrobial therapies for Q fever.

Q fever is caused by the bacterium Coxiella burnetii and has both acute and chronic forms. The acute disease is a febrile illness often with headache and myalgia that can be self-limiting, whereas the chronic disease typically presents as endocarditis and can be life threatening. The normal therapy for the acute disease is a 2 week course of doxycycline, whereas chronic disease requires 18-24 months of doxycycline in combination with hydroxychloroquine. Alternative treatments are used for pregnant women, young children and those who cannot tolerate doxycycline. Doxycycline resistance is rare, but has been reported. Co-trimoxazole is a currently recommended alternative treatment, but quinolones, rifampin and newer macrolides may also provide some benefit.