Comparative study of three tests (indirect haemagglutination, direct agglutination, and indirect immunofluorescence) for detection of antibodies to Toxoplasma gondii in pregnant women.

Sera of 600 asymptomatic pregnant women were tested by IHAT for Toxoplasma antibodies. The positive reactors were further tested by IFAT and direct agglutination test (DAT). The prevalence of Toxoplasma antibodies was found to be 27.3% by IHAT, and 58.5% of those found positive were also positive by IFAT, while only 51.8% of them were positive by DAT with 71.34% degree agreement between both tests. So, IFAT was found to be more sensitive than DAT in reference to IHAT and is recommended as a confirmatory test for those found positive on screening by IHAT, DAT, compared to IFAT, gave 69.7% sensitivity and 73.5% specificity. Results support previous findings that IHAT, IFAT and DAT measure different antibodies of Toxoplasma gondii.