[Q fever].

Q fever is a zoonosis caused by Coxiella burnetii. The infection is transmitted to humans mainly through aerosols generated from products of delivery of cows and other animals. Generally the disease presents acutely with fever, pneumonitis and hepatitis. But chronic endocarditis is also a possible occurrence. Diagnosis is usually made by serology. The acute form of the infection responds well to tetracyclines and other antibiotics. But endocarditis is difficult to treat, and its prognosis is grim.