Dr. Murai Éva - Gubányi András szerk.: Parasitologia Hungarica 29-30. (Budapest, 1997)

accurately by serological methods, all the "acute" cases were regarded and treated as possible cases of congenital toxoplasmosis. Seronegative cases were retested every second month until the end of pregnancy to monitor any seroconversion. PCR amplification of part of the P30 gene of T. gondii (Verhofstede et al. 1993), Western blot analysis (Verhofstede et al. 1988, Szénási et al. 1990), and/or anti-P30 IgA, IgM determinations (Decoster et al. 1992, Szénási and Nagy 1996a, Szénási et al. 1996b) were also carried out from fetal blood and amniotic fluid. RESULTS AND DISCUSSION Main points of the total screening program between 1987 and 1995 Between 1987 and 1995, we screened 19,985 pregnant women (Table 1). Of them, 12,473 were found to have moderate (1:16-1:128) CFT titres (seropositive subjects, Group B). This means that they had had infection before the pregnancy ("chronic" infection). Thus, they are "immune" and have no chance of getting toxoplasma infection during pregnancy. The average prevalence rate was 62.4% and varied from 55.2% in 1994 to 73.2% in 1991 (Group B). A total of 7,512 women (37.6% of those screened during the study) were seronegative at the first test (Group A). Of them, however, 11 patients were found to develop anti-toxoplasma antibodies later, during their pregnancy, thus constituting the seroconverted group (Group C), ranging from 0 in 1991 and 1993 to four (0.45%) in 1989. These patients had been definitely infected during their pregnancy, thus, their fetuses have a high chance of acquiring the infection from their mothers. The yearly distribution of Group D (high initial antibody levels [HIAL] with anti-P30 IgA) varied from three (0.24%) in 1990 to 26 (2.16%) in 1995. Altogether, 114 patients belonged to that group of "acute" toxoplasmosis. The number of patients in Groups C+D varied from 5 in 1988 and 1990 (0.22% and 0.23%, respectively) to 27 cases (1.29%) in 1995. Thus, a total of 115 patients (Groups C+D) were found with serological evidence of "acute" toxoplasmosis. The treatment of these mothers was started as soon as the high antibody titres were discovered, and their babies were also treated for 1 month after delivery and followed up for at least 2 years (Table 1). Table 2 shows a typical antibody pattern characteristic of those babies (altogether 115) who were born to mothers with the strong suspicion of having "acute" toxoplasmosis. Due to the appropriate treatment, none of the 115 neonates at risk of congenital toxoplasmosis have ever developed high antibody titres or clinical signs of toxoplasmosis. Analysis of the congenital toxoplasmosis screening program carried out in 1995 A total of 2,091 pregnant women's sera were screened in 1995 as described above. Table 3 shows that 889 of them were seronegative, i.e. their CFT titre was < 1:16 (Group A, 42.5%). In 1995, 1,202 pregnant women were found to be seropositive at the first screening, i.e., their CFT titres were > 1:16 (Group B, 57.5%). Higher titres were found in a gradually decreasing number of cases. In 1995, one case of seroconversion was recorded (Group C, 0.11%), while 26 persons belonged to the HIAL category (Group D, 2.16%). These values do not deviate significantly from those found in the previous years (see Table 1). As shown in Table 4, by a further dissection of Group A versus Group B into different age categories (15-19, 20-24, 25-29, 30-34, > 35 years, respectively, and "age is not