Seroprevalence and molecular investigation of toxocariasis in working children and control group in Tehran, Iran

Background: Toxocariasis, a zoonosis helminthic disease is caused in humans by Toxocara canis and Toxocara cati with worldwide distribution. In this study the seroprevalence and molecular toxocariasis were investigated in the working children and the control group in Tehran, Iran. Methods: In total, 468 children between the ages of 7-14 years old, including 280 blood samples from working children and 188 samples from control group children were collected from Tehran. ELISA test was performed to detect IgG antibody against Toxocara canis. Molecular tests using ITS2 primer were performed to determine the status of toxocariasis infection in children. Results: The seroprevalence of toxocariasis was 24 (8.6%) and 10 (5.3%) in the working children and control group respectively. Seroprevalence of toxocariasis in girls 18(13.5%) was higher than boys 6(4.1%) in working children and differences was statistically significant. A significant relationship was found between contact with soil or contact with cats and dogs and the seroprevalence of toxocariasis in working children. No amplification of the target DNA was detected in plasma or whole blood samples in working children and the control group with Toxocara canis and cati primers. Conclusion: The seroprevalence of IgG antibody against Toxocara canis was higher in working children than in the control group in Tehran. The result of the present study indicated a significant difference between working children and the control group in terms of Toxocara canis antibody titer. More contact with soil in these children and contact with dogs and cats may be factors in acquiring toxocariasis in the children.