Antibodies to Borrelia burgdorferi in various population groups in Croatia.

The purpose of the present study was to investigate the prevalence of antibody to Borrelia burgdorferi in Croatia in various population groups. The study comprised 263 individuals: 93 healthy subjects (travellers); 100 controls separated into 2 subgroups, 50 from high risk zone (endemic) and 50 from low risk zone (non-endemic); and 70 members of a high risk population (forestry workers). Antibody to B. burgdorferi of IgM and IgG class were analysed by an ELISA technique using mixed antigen made of strain B31 (ATCC 35210). IgG antibodies were detected in 9/93 (9.7%) in general population; 22/50 (44.0%) in the control group from high risk zone and 4/50 (8.0%) from low risk zone; and 30/70 (42.9%) among forestry workers. In all tested groups low numbers of IgM positive were found.