Summary. An analysis is made of the antibody response to Phase-1 and Phase-2 antigens, as measured by immunofluorescence in the IgM, IgG or IgA immunoglobulin classes, or by complement-fixation, in patients with acute and chronic Q fever and in vaccinated or skin-tested subjects. In acute (primary) Q fever, IgM specific antibodies to Phase-1 antigen are present in early convalescence together with IgM, IgG, IgA and CF antibodies to Phase-2 antigen. IgM specific antibody may persist for at least 678 days after onset of the acute illness. Patients with chronic Q fever have no IgM specific antibody to Phase-1 or -2 antigens, or only at very low levels; high levels of specific antibody in the IgG and IgA classes, together with CF antibody to both antigenic phases, appear to be characteristic. The serological response in initially seronegative, vaccinated subjects is mainly to Phase-1 antigen in the IgM fraction, and to a lesser degree to Phase-2 antigen by CF and in IgM and IgG classes. Subjects who were equivocally seropositive before vaccination showed IgA and IgG specific antibody responses to Phase-1 antigen and CF and IgG class responses to Phase-2 antigen. Similar antibody profiles were observed in patients who seroconverted after a positive skin-test. Data are also presented on the suitability of antigens for use in immunofluorescence and on the binding of IgM specific antibody by Phase-1 antigen but its failure to fix complement.


Article metrics loading...

Loading full text...

Full text loading...


Most cited this month Most Cited RSS feed

This is a required field
Please enter a valid email address
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error