Prevalence of parasites in soil samples in Tehran public places

Abstract

The aim of this study was to determine the prevalence of all parasitic forms (eggs, larvae, cysts and oocyst) by using two flotation methods in soil of public places and children’s playgrounds in Tehran City, Capital of Iran. During 2008 to 2009, 150 soil samples were collected from various sites by simple random selection. To recover parasites, the soil samples were examined by sodium nitrate flotation, sucrose flotation method. The McNemar test and Kappa Index were used to analyse the statistical significance of the results. The prevalence of soil parasites was as follows: Toxocara spp. eggs in sodium nitrate flotation (38.7%) and in sucrose flotation method (33%), Isospora spp. in sodium nitrate flotation (10.7%) and in sucrose flotation method (18.7%), nematode larvae in sodium nitrate flotation (40.7%) and in sucrose flotation method (24%), Eimeria spp. in sodium nitrate flotation (8.7%) and in sucrose flotation method (24.7%), Coccidian oocyst and Sarcocystis spp. in sodium nitrate flotation (27%) and in sucrose flotation method (42%), Dicrocoelium dendriticum in sodium nitrate flotation (2.7%) and in sucrose flotation method (2%), Geohelminths in sodium nitrate flotation (6.7%) and in sucrose flotation method (3.4%). Furthermore, following sucrose flotation method  performance, modified Ziehl-Neelsen staining technique was done and oocysts of Cryptosporidium spp. was detected in 15 (10%) of soil samples. According to McNemar test, the sodium nitrate flotation and sucrose flotation method statistically were differed to parasites detection. Results of our findings provide evidence that soil may play an important role in transmission of zoonotic parasite diseases to human. In addition, control of high population of animals such as stray dogs and cats is necessary to reduce the distribution of parasites.

Key words: Prevalence, parasites, flotation method, Tehran.