ELISA and Rapid Test Based Detection Rate of Anti-Toxoplasma Antibodies Among Pregnant Consulting Maternity Hospital in Duhok City, Iraq

Abstract

Background: Toxoplasma gondii is a protozoan parasite that affects approximately one-third of the global human population. Cats are the definitive hosts, whereas humans and most herbivores are intermediate hosts. Humans acquire infection through the ingestion of undercooked meat from infected animals or exposure to cat faeces containing the infective stage of the parasite. Infection during pregnancy carries a risk of intrauterine foetal transmission, which may lead to abortion or congenital toxoplasmosis with subsequent complications. Aims and Objectives: This study aimed to estimate the exposure rate to the parasite and evaluate associated risk factors among pregnant women, a high-risk group, and to compare the results obtained using the highly sensitive and specific ELISA method with those obtained using a rapid test with lower sensitivity and specificity. Materials and Methods: A total of 344 fresh blood samples were collected from pregnant women attending the maternity hospital and tested using both ELISA and rapid diagnostic serological tests for IgG antibody detection. Results: Of the 344 samples, 63 (18.31%) were seropositive for IgG using the rapid test, whereas 61 (17.73%) were positive using ELISA. Only 53 samples were positive using both diagnostic tests. None of the assessed risk factors showed a statistically significant difference. Compared with ELISA, the rapid diagnostic test showed a high negative predictive value (97.2%) and a low positive predictive value (84.1%), with a sensitivity of 86.9% and a specificity of 96.5%. Conclusion: The rapid diagnostic test showed a low positive predictive value. Therefore, to minimise congenital transmission of maternal toxoplasmosis to newborns, both positive and negative rapid-test results in pregnant women, particularly positive results, should be followed up and confirmed using the more specific and sensitive ELISA method.