A survey on the seroprevalence of toxocariasis and related risk factors in Eosinophilic children of Northwest Iran

Background: Toxocariasis is a serious zoonotic helminthic disease caused by the nematodes; Toxocara species. Aim: A cross-sectional study was conducted to determine the seroprevalence of toxocariasis and related risk factors in eosinophilic children referred to the pediatrics hospital of Qazvin province northwest Iran during 2019-2020. Methods: A total of 200 blood samples were collected from eosinophilic children referred to the Qods Pediatrics Hospital. Demographic data, clinical symptoms, and dogs-and soil-contact history were collected. The presence of anti-Toxocara IgG antibody was evaluated by T. canis IgG ELISA kit. Results: Anti-Toxocara IgG antibodies were detected in 14 (7%) of the total eosinophilic children. The seropositive rate of toxocariasis in hyper-eosinophilic children (>1000/mm(3)) was 15.1%, while the seropositivity was 4.1% in children with eosinophilia status (500-999/mm(3)). There was a significant association between the eosinophilia rate and seropositivity (P<0.05). Also, seroprevalence in asymptomatic eosinophilic children was 4.4%, while in children with clinical symptoms it was 17.1%. Accordingly, a statistically significant difference was found between clinical symptoms and Toxocara infection (P<0.05). Conclusion: The prevalence of toxocariasis in eosinophilic children is a serious health problem in the study area. Therefore, serologic evaluation for the diagnosis of Toxocara infection is recommended for eosinophilic children.