SEROLOGIC RESPONSE TO RICKETTSIAL ANTIGENS IN PATIENTS WITH ASTRAKHANFEVER

Astrakhan fever is a new spotted fever group (SFG) rickettsiosis. Sera of patients with Astrakhan fever have been examined by microimmunoflu orescense and western immunoblotting to determine the serologic respon ses to the Astrakhan strain and to R. conorii M-1 strain and the Israe lian isolate of SFG rickettsiae. The serologic response to specific ri ckettsial agent and to Israelian isolate has been found to be similar, but was different of that to R. conorii. Immunoglobulin G (IgG) and I gM antibodies were detected inmost sera and were directed against the lipopolysaccharide. Only one of tested sera contained IgG antibodies w hich also recognized high molecular weight proteins.