Frequency of antitoxocara antibodies in students with chronic cough and eosinophilia in a rural area of Shiraz, Iran

ABSTRACT

Visceral larva migrant's syndrome by toxocara affects mainly children between 2 and 5 years old, it is generally asymptomatic, and the seroprevalence varies from 3 to 86% in different countries; as well as, the secondary stage larvae cause ocular, respiratory and neurotic disorders. The aim of this study was to determine the incidence of anti-toxocara antibodies in children blood that showed chronic cough having eosinophilia in rural part of Shiraz, Iran. In a cross sectional study during a tuberculin survey rural area of Shiraz, a city in Southwest Iran, a number of 610 children were selected by randomized two-stage cluster sampling. Children with chronic cough were investigated for toxocariasis. Initially, the absolute eosinophil count was determined. Then, children having eosinophilia were tested by toxocara-IgG - ELISA kit [Ibl, Hamburg]. Of total 80 children with chronic cough, 12 [15%] were eosinophilic, among them 6.25% were hypereosinophilic, 9 [11.25%] were toxocara ELISA-IgG positive. No correlation between intestinal parasites and toxocariasis was detected. There was also no significant interdependence between age, gender, and dwelling difference in toxocara antibody amount. Presence of eosinophilia and the risk factors evaluated in this population were frequently associated to human toxocariasis. Anti toxocara antibody was detected in more than half of children with chronic cough, thus, toxocariasis among children in schools should have been noticed in schools by both education and hygiene ministry