Q-fever endocarditis in England and Wales, 1975-81.

Endocarditis was recorded in 92 (11%) of 839 confirmed Q-fever infections reported for the Communicable Disease Report by laboratories between 1975 and 1981; Q-fever endocarditis accounted for approximately 3% of all cases of endocarditis reported. Two-thirds of the 92 reports were of men, and in both men and women endocarditis affected mainly young and middle-aged adults. Only one-third of Q-fever endocarditis patients were noted to have an underlying heart-valve lesion. There were also 30 reports of chronic Q-fever infection, and in 10 the primary clinical feature was liver disease. The laboratory data do not support the view that Q-fever endocarditis is a rare compilation of Coxiella burnetii infection, and the condition may be considerably underdiagnosed. Joint veterinary and medical investigations should be undertaken to establish the natural history of Coxiella burnetii infection in the U.K. in order to formulate policies for prevention of acute and chronic infection.