Background and Objectives: Toxocara canis is the most common intestinal nematode of dogs and the chief cause of visceral larva migrans (VLM/Toxocariasis) in man particularly children. Regarding the high prevalence of the parasite in dogs, parasite-infested park soil of the area and lack of background data, the present study was carried out to determine the seroprevalence of the disease in children under the age of ten in urban and rural areas of Hamadan in 2002.
Materials and Methods: This descriptive study was implemented on 544 children under the age of ten (408 children in urban and 136 children in rural areas) through cluster random sampling. After taking blood samples of 2-2.5 ml testing by ELISA with Toxocara canis excretory-secretory antigens were used to determine the positive cases. For evaluation of results Index Positivity (I.P) was used and the samples with I.P above 1.1 were considered positive. The results were analysed through descriptive statistics and 2 test.
Results: Seroprevalence of the disease was found to be 5.3%.In 19 people (3.5%) amount of antibody was at medium range and in 496 people (91.2%) it was negative. Of 29 positive children 14 people (5.3%) were males and 15 people (5.6%) were females. In addition, 23 people (5.6%) were urban residents and 6 people (4.4%) were rural residents. Of 29 above mentioned children 3 people (5.7%) were in the age group of 1-3 years, 14 (5.3%) in 4-6 years and 12 (5.3%) in 7-9 years. Association of age groups with infection was not significant statistically.
Conclusion: Despite the fact that the positive titer of ELISA is not an appropriate index for diagnosis of non symptomatic toxocariasis in areas with low prevalence, the present study reaffirms the considerable prevalence of toxocariasis as a public health problem.