Q fever.

Q fever is endemic throughout much of Australia and is most frequently seen in abattoir workers, farmers and veterinarians. Initially, there is a febrile, influenza-like illness. The infection is usually self-limited within several weeks, but rarely patients may develop infective endocarditis or hepatitis. The diagnosis is usually confirmed by finding risings titres of antibodies specific for C. burneti. The infection is not very responsive to treatment, but if tetracycline is administered early, the duration of fever is shortened.