Comparison of the prevalence of Toxocara spp. eggs in public parks soils in different seasons, from 2017 to 2018, Tehran Province, Iran

Abstract

Background and objectivesToxocariasis is one of the most important pathogens transmitted to humans through the soil. Temperature 12–37 °C provides the best conditions for infecting eggs to be transmitted to humans, dogs, and other hosts. This study is preliminary in order to detect Toxocara eggs in public park soils and to study the correlation between seasons and climate variation with contamination rate. MethodologyA total of 1132 soil samples were collected over the course of the year, from 11 major parks. A centrifugal-floatation technique with the utilization of saturated sodium nitrate solution was used to examine the soil samples to recover Toxocara spp eggs. ResultsOut of 1132 samples collected from public park soils, 129 (11.39%) samples were positive for Toxocara spp eggs, Laleh Park in south part showed the highest contamination rate. Contamination rate varied according to the site of parks, location with the highest rate in the south followed by center and the prevalence of eggs is high in spring and autumn without significant association. The prevalence of Toxocara spp eggs in soil associated significantly with Average temperature and rainfall (P = 0.04, 0.001 respectively). ConclusionAccording to our study findings, soils of the public parks in Tehran showed as one of the main sites for contamination with Toxocara spp eggs. The prevalence of soil contamination varied according to a climate of different seasons, spring and autumn climate such as temperature and rainfall rate were considered as optimal condition for eggs development and to survive.