a1 Department of Microbiology and Public Health Laboratory, Derriford Hospital, Plymouth PL6 SDH
a2 Regional Department of Virology and Public Health Laboratory, Myrtle Road, Kingsdown, Bristol, BS2 8EL
Between 1972 and 1988 we have serologically confirmed 103 Coxiella burnetii infections: 46 were acute, 5 were chronic, 52 represented past infections. Details of 61 cases are presented.
Of acute cases 80 % had respiratory involvement; at least 63 % had pneumonias. The incidence (22%) of neurological complications was of particular interest; 40% of these patients had prolonged sequelae. One acutely ill patient died of fulminating hepatitis. Patients with pre-existing pathology or immunosuppression were especially susceptible to C. burnetii.
In the absence of acute sera, the complement fixation test alone provided inadequate differentiation between recent and past Q fever: phase II titres persisted at ⋝ 80 for more than 1 year after the acute infection in 15 cases; maximum duration of persistence was 14 years. Three patients acquired high phase I titres.
Only 5% of cases had chronic Q fever, but in view of the diverse sequelae observed in this series, we suggest that long-term serological and clinical follow-up of all cases of Q fever is fully justified.
(Accepted April 25 1990)