Prevalence of antibodies to Toxoplasma gondii in the female population of the County of Split Dalmatia, Croatia.

The prevalence of IgG antibodies reactive with Toxoplasma gondii in the female population of the County of Split Dalmatia was investigated by enzyme linked immunosorbent assay. Of a total of 1109 serum samples collected from female subjects, 423 (38.1%) reacted with T. gondii. The frequency of positive sera increased with age. Theoretical incidence of congenital toxoplasmosis was calculated from the annual increase in cumulative prevalence of antibodies between different age groups among the women of childbearing age. The estimated theoretical incidence of congenital toxoplasmosis was 1.4 per 100 pregnancies of adolescents (16-20 years) and decreased to 0.1% in seronegative pregnant women aged 41-45.