Comparative Assessment of Toxoplasma gondii Infection Prevalence in Romania Using 3 Serological Methods

The aim of this study was to evaluate three serological tests used for T. gondii antibodies detection in horses. A commercially available ELISA test (ID Screen Toxoplasmosis Indirect Multi-Species, ID.vet, Innovative Diagnostics, France) and two ‘in house’ methods, indirect immunofluorescent antibody test (IFAT), modified agglutination test (MAT) were compared for their sensitivity and specificity in detection of anti-T. gondii antibodies in naturally infected horses using as standard cumulative seropositivity. Also, their agreement was evaluated by kappa statistic. A good correspondence of test results was observed. The best agreement was seen between ELISA and MAT (k=0.77). ELISA has the higher sensitivity (96.8%) and also the higher specificity (96.1%), followed by MAT (90.3 and 94.1, respectively) both tests proving better diagnostic potency compared with IFAT. The highest seroprevalence was obtained by ELISA (39%), followed by MAT (37.8%) and IFAT (34.1%). Based on our results, we recommend the utilization of indirect ELISA and MAT for detection of T. gondii antibodies in horses.