RESUMEN
Intestinal parasites, esp. giardiasis are the most common gastrointestinal infection disorders in the world, especially in north of Iran. The aim of present study was to determine the prevalence of parasitic infections in the stool samples of the people living in the central areas of Mazandaran province. In this descriptive study, 4223 human fecal samples were randomly collected from different areas in different seasons in the central regions of Mazandaran province, from Oct 2009 to Sept 2010. The Samples were assessed by direct smear and formalin-ether method. We analyzed the data by using Chi-square and T test. Of 4223 stool samples, 75 [17.9%] have at least one type of parasite. The rate of infection with intestinal protozoa is 15.9% including 8.1% with B. Hominis, 6.4% with G. lamblia, and 1.9% with intestinal worms [S. stercolaris and Strongyloides larvae] .The prevalence rate is 6.1% in rural, 5.9% in urban and 5.8% in mountainous areas. Considering the seasons, the prevalence in the urban area in summer [4/39%], rural area in spring [32%] and mountainous area in fall [28%] are reported. Statistically no significant differences between different regions and seasons have been observed [P> 0.05]. Based on the prevalence of intestinal parasitic infections, especially in the central part of Mazandaran province in different seasons, early diagnosis and treatment of the patients and public health promotion could be effective to prevent and control these infections in north of Iran