Intestinal parasitic infections are amongst the most common infections worldwide. It is estimated that 450 million are ill as a result of these infections, the majority being children [1,2]. These intestinal parasitic infections are found among people with low socio- economic status and poor hygiene [3,4]. Intestinal parasitic infections considered as major problems of public health in developing countries. In developed countries intestinal protozoan parasites are known as an important cause of gastrointestinal disorders , enteric protozoa are one cause of diarrheal disease in children. Intestinal parasitic infections mainly are transmitted by the fecal-oral route [3,6]. Common intestinal parasites such as Giardia intestinalis (G. intestinalis) and Blastocystis hominis (B. hominis) are still health challenges of economically developed and developing countries [7,8]. B hominis is the most common human intestinal protozoa worldwide. It was associated with diarrhea in the tropics and subtropics, since it was found in patients throughout the world. The reported prevalence rates of intestinal protozoa varied from 1.5% to 10% in developed countries, with much higher rates of 30%to 50% in developing countries [9,10].
Two hundred million intestinal parasitic protozoan occur each year in Africa, Asia and Latin. America . Intestinal parasitic infections especially protozoa are historically common in Iran. Several studies have been conducted on the distribution and prevalence of several intestinal parasitic infections in Iran [12,13]. There are still several regions for which epidemiological information is not available. So, for the first time, we conducted this study to determine the prevalence of intestinal parasitic infections in Chelgerd, Iran.
Materials and Methods
Study area: Chelgerd is a township in province of ChaharMahal and Bakhtiari in southwest of Iran. This descriptive cross-sectional type of study was carried out upon the inhabitant and tribe populations with various complaints of gastrointestinal disorders from April 2008 to October 2009 in Chelgerd, Iran. This area is surrounded by the Zagros Mountains. Temperature in spring and summer is temperate and in winter is very cold (0oC-20oC). In spring, tribe societies migrate from Khuzestan province (south of Iran) to Chelgerd city (southwest of Iran).The people who live in this region are generally engaged in animal husbandry and agriculture.
A total of 655 stool samples were studied from April 2008 to October 2009. Stool samples from 311 inhabitants and 344 tribes, who visited Chelgerd central health care, Iran were collected and examined by three parasitological methods in Chelgerd laboratory.
This study was approved by Medical School Council of Isfahan University of medical sciences.
The data were analysed by SPSS software through descriptive statistics, frequency tables, and chi-square test. P-value of less than 0.05 was considered as statistically significant.
Collection of stool samples
Six hundred and fifty five fecal samples were randomly collected in three days. Inclusion criteria in this study were patients with abdominal pain, fever, tenesmus, diarrhea and dysentery .Some of them had only one symptom and some others had more than one symptom. An informed consent form was signed by participants (in cases under 18-year-old, it was signed by their parents).
In order to get more information about intestinal parasitic infections, they were asked to fill out a questionnaire form about age, life style, locality (tribes, inhabitant) and gender. The stool samples which were contaminated with urine or soil were excluded from the study.
Stool examination: Samples were examined microscopically by Direct smear with normal saline and iodine, Formol-ethyl acetate concentration and Trichorom staining methods .
A total of 655 stool specimens were examined by three parasito-logical methods, out of which 367 (56%) samples were positive for intestinal parasites. A total of 134 (43%) out of the 311 stool samples from inhabitants and 233 (67.7%) out of 344 stool samples of tribe populations were positive for at least one intestinal parasite. There was significant difference in intestinal parasitic infections between inhabitants and tribes (p=0.001) [Table/Fig-1].
Out of 655 stool samples were examined, 361(55.1%) samples revealed intestinal protozoan parasite and 6(0.9%) showed helminth eggs. The overall prevalence of intestinal protozoan infections in both of the populations was due to G. intestinalis (28.2%) and B. hominis (27.5 %) [Table/Fig-2].
[Table/Fig-3] shows the prevalence of intestinal protozoan infections among all the patients by gender. Although, the infection was more frequent in females than males, it was no statistically significant (p=0.523). The highest infection rate of intestinal parasites was in the 0-9 years old age group (18.9%) and the lowest infection rate was in the 50-59 y age group (0.6%).There is no statistically significant difference between them (p>0.05) [Table/Fig-4]
Multiple infections (polyparasitism) occurred in 158 individuals (24.1%). Among all the subjects, frequency of Double infection was 104 (15.87%), and that of triple infection was 43 (6.56%) and those of more than three infection was 11(1.67%)[Table/Fig-5].
Intestinal parasitic infections of humans are major health problem in many tropical and sub-tropical areas of the world, especially in the developing countries such as Iran. Several epidemiological studies have been conducted to determine the prevalence rate of intestinal parasite infections in Iran [15-18]. Patterns of intestinal parasitic infections in the population, may have changed because of socio- demographic characteristic, life style, human behaviour, nutritional habituate and sanitary/ hygiene improvements [15,19,20]. Prevalence of intestinal parasites varies in different parts of Iran, with 61% reported from Yazd (central of Iran), 56.6% in Ghazvin (North of Iran) and 46.7% in Ilam (West of Iran) .
Prevalence of intestinal parasitic infections in this area hasn’t clearly been determined, so the study was conducted to determine the prevalence of intestinal parasitic infections in this part of Iran, for the first time. The present study revealed that the tribe populations had a higher prevalence of intestinal parasitic infections (67.7%) as compared to the inhabitant population (43%). This finding was in agreement with the findings of KD et al., .
Out of 655 patients who were studied, 361(55.1%) are infected with at least one species of intestinal protozoa and 6(0.9%) patients infected with helminth. Relatively low incidences of helminthic infections achieved in this study, is in accordance with the fact that the prevalence of intestinal helmints appear generally to become rarer in Iran and we only found Hymenolepis nana in 6 (0.9%)of the examined samples . This contradiction is due to this fact that intestinal protozoa cysts are more easily transmissible from one person to another one than helminthes. Intestinal protozoa cysts are more resistant to disinfectant agents and unfavorable conditions than helminth eggs and larva. In this study, 9 species of intestinal pathogenic and non-pathogenic protozoa were detected and they were as follow: Giardia intestinalis 185(28.2%), Blastocystis hominis 180 (27.5%), Endolimax nana 97(14.8%), Entamoeba coli 74 (11.3%), Iodamoeba butschlii 31(4.7%), Entamoeba histolytica/ E. dispar 11(1.7%). They are major public health concern in both populations.
The highest infection rates of intestinal pathogenic protozoan were due to Giardia intestinalis followed by Blastocystis hominis. The findings of this study show a trend of high risk infections of intestinal protozoan among these populations especially in tribes as shown by other studies [15,19-21].
Public health interest in Giardia intestinalis is increasing because of the growing recognition of its role as a cause of disease outbreak. It is the most common infection throughout countries with temperate and tropical climate. The prevalence rate of Giardiasis was 2-5% in developed countries and 20-30% in developing countries .
A similar study carried out by Arani et al., showed the prevalence of intestinal parasites in a population in south of Tehran. Out of 4371 participants, 466(10.7%) were infected with at least one intestinal parasites. The most prevalent parasites were Blastocystis hominis and Giardia intestinalis .
During 2004-2005, a study in rural population of Mazandaran Province, northern Iran, was carried out to achieve the profiles of distribution of intestinal protozoan parasites. .The results showed that Giardia intestinalis (10.2%) and Blastocystis hominis (9.8%) were the most frequent intestinal protozoan parasites .
The most prevalent intestinal protozoa parasites in 228 school attending children of Isfahan, Iran was due to Giardia intestinalis (19.3%) . A similar study in Thailand on guardian-less children showed that the prevalence of Giardia intestinalis was 37.7% . A study was conducted in Libya to determine the prevalence and clinical features of Blastocystishominis infection among patients in Sebha. B. hominis was found in 969 (26.58 %) of 3645 stool specimens examined .
In the present study, the highest infection rate was found in children between 0-9 years old compared to other age groups while there was a reduction in infection as age increased. It could be due to higher awareness in observing personal hygiene measures between older age group. Some studies proved that the infection rate in children (under-15) increased with age and there is no statistical significance between genders .
In this population, female do a lot of works such as household, animal husbandry and agriculture. Although the infection rate was more frequent in females than males, there was no significant difference in prevalence of intestinal parasitic infections between males and females (p=0.5).
In this study, 24.1% of the total examined subjects have co-infection with more than 1 species of intestinal parasites. These results show that the rate of intestinal parasitic infections is high in these populations. This is similar to a study done in Argentina portraying a polyparasitism of 61.6% among marginally poor people . This finding is consistent with a study done among urban dwellers in southwest Ethiopia. Multiple infections (polyparasitism) occurred in 515 individuals making 56.7% of the total examined subjects and 68.3% of those who had intestinal parasites. Double infection was frequently seen in more than one third (35.8%) among Ethiopian subjects .
Personal hygiene among these aboriginal populations especially in tribes is poor. The children in this region tend to have special habits such as not washing hands before and after eating, consuming raw food especially fruits without washing them, play on soil and defecating on it. These habits are also common among adults. They are some factors for high prevalence of intestinal protozoa especially in tribes. In this region, tribes are tent-dweller and because of this, they have no easy and hygienic place for the disposal human excreta and they do not access to hygienic facilities. They never use toilet and latrines and indiscriminate defecation which spreads parasites in the immediate environment (soil, courtyard).In addition, the flowing of sewage into rivers can cause water contamination.
Based on our observations, we found that although the government provided piped water from the river for inhabitants. Sometimes water contaminated with sewage and people who drink it, will become infected. It actually happens because water distribution system in this region is very old and pipe break commonly occur and consequently sewage and soil penetrate into water and it can cause water contamination.
Prevalence of intestinal parasitic infections among the inhabitants and tribes of Chelgerd city, Iran, 2008-2009
|Ethnic group||Total no.||Positive no.||p-value|
Distribution of intestinal protozoa infections among the inhabitants and tribes of Chelgerd city, Iran, 2008-2009
|Type of intestinal protozoan parasites||Infective Tribes n(%)||Infective Inhabitant n(%)||Total n(%)|
|E. histolytica/ E. dispar||8(2.3)||3(1)||11(1.7)|
Prevalence of intestinal parasitic infections among male and female in the inhabitants and tribes of Chelgerd city, Iran, 2008-2009
|Sex||Total no.||Infective no.||p-value|
Prevalence of intestinal parasitic infections by age groups among the inhabitants and tribes of Chelgerd city, Iran, 2008-2009
|Age||Non-infective||Infective||Total percent of infective Patient|
Frequency of co-infection with more than 1 species of parasite among the inhabitants and tribes of Chelgerd city, Iran, 2008-2009
|More than 3 species of parasites||11||1.67|
The high prevalence of intestinal parasitic infections in the area under study indicated that much work remains to be done to improve the health of the people. Screening and treatment of infected people as well as improving sanitation and supplying treated water will lower the infection rates. Aborigine people especially children, should be educated about environmental and personal hygiene.
This study was approved with Grant no.388036 and financially supports by the vice chancellery of Isfahan University of Medical Sciences. The authors of this study acknowledge deputy of research and technology of Shahrekord University of medical sciences.
. A Haileeyesus, P Beyene, intestinal protozoan infections among HIV positive persons with and without Antiretroviral Treatment (ART) in selected ART centers in Adama, Afar and Dire-Dawa,Ethiopia. Ethiopiaj Health 2009 [Google Scholar]
. N Vahid, E Kasra, K Gholamreza, N Mehdi, A Omid, Intestinal parasitic infections among inhabitants of Karaj city, Tehran province Korean J Parasitol 2009 47(3):265-68. [Google Scholar]
. P Ayeh-Kumi, S Quarcoo, G Kwakye-Nuako, J Kretchy, A Osafo-Kantanka, S Mortu, Prevalence of Intestinal Parasitic Infections among Food Vendors in Accra, Ghana J Trop Med Parasitol 2009 32:1-8. [Google Scholar]
. RA Sehgal, V Gogulamudi, JV Jaco, V Atluri, R Subba, Prevalence of intestinal parasitic infections among school children and pregnant women in a low socio-economic area, Chandigarh, North India. Research Article 2010 1(2):100-03. [Google Scholar]
. R Haque, Human Intestinal Parasites Health Popul Nutr 2007 25(4):387-91. [Google Scholar]
. A Singh, E Houpt, W Petri, Rapid Diagnosis of Intestinal Parasitic Protozoa, with a Focus on Entamoeba histolytica Interdisciplinary Perspectives on Infectious Diseases 2009 8 [Google Scholar]
. A Shojaei, R Alaghehbandan, LS Akhlaghi, A Rastegar, Prevalence of intestinal parasites in a population in south of Tehran, Iran Rev Inst Med Trop Sao Paulo 2008 50(3):145-49. [Google Scholar]
. M Moshira, F Helmy, S Hisham, A Fattah, L Rashed, Real-time PCR/RFLP assay to detect Giardia intestinalis genotypes in human isolates with diarrhea in Egypt J Parasitol 2009 95(4):1-5. [Google Scholar]
. J Borges, R Alarcon, V Neto, E Gakiya, [Intestinal parasitosis in Indians of the Mapuera community (Oriximina, State of Para, Brazil): high prevalence of Blastocystis hominis and finding of Cryptosporidium sp and Cyclospora cayetanensis Revista da Sociedade Brasileira de Medicina Tropical 2009 42:348-50. [Google Scholar]
. A Daryani, M Sharif, M Nasrolahei, A Khalilian, A Mohammadi, G Barzegar, Epidemiological survey of the prevalence of intestinal parasites among schoolchildren in Sari, northern Iran Trans R Soc Trop Med Hyg 2012 106(8):455-59. [Google Scholar]
. MY Noor Azian, YM San, CC Gan, MY Yusri, Y Nurulsyamzawaty, AH Zuhaizam, Prevalence of intestinal protozoa in an aborigine community in Pahang, Malaysia Tropical biomedicine 2007 24(1):55-62. [Google Scholar]
. E Kia, M Hosseini, M Nilforoushan, A Meamar, M Rezaeian, Study of Intestinal Protozoan Parasites in Rural Inhabitants of Mazandaran Province, Northern Iran Iranian J Parasitol 2008 3(1):21-25. [Google Scholar]
. H Taherkhani, S Shariati, Clinical Manifestations Of Giardiasis In Iran Journal of Clinical and Diagnostic Research 2009 3:1416-18. [Google Scholar]
. G Donato, M Esparar, Y Vicente, J Belizario, J Relos, Prevalence of Intestinal Parasitic Infections among Food Handlers of a Tertiary Hospital in Manila using Direct Fecal Smear and Formalin Ether Concentration Technique Phil J Microbiol Infect Dis 2004 33(3):99-103. [Google Scholar]
. GR Mowlavi, H Mir-Ahmadi, M Rezaeian, E Beigom-Kia, N Ebrahimi-Daryani, MB Rokni, The Prevalence of Intestinal Parasites in Tribal Parts of Khuzestan Province Scientific Journal of the Iranian Association of Gastroenterology and Hepatology (Govaresh) 2008 12(4):219-28. [Google Scholar]
. l Akhlaghi, J Shamseddin, A Meamar, E Razmjou, R Oormazdi, Frequency of Intestinal Parasites in Tehran Iranian J Parasitol 2009 4(2):44-47. [Google Scholar]
. A Haghighi, SA Salimi Khorashad, E NazemalhoseiniMojarad, B Kazemi, M Rostami Nejad, S Rasti, Frequency of enteric protozoan parasites among patients with gastrointestinal complaints in medical centers of Zahedan Tropical Medicine and Hygiene 2009 103:452-54. [Google Scholar]
. K Hazrati Tappeh, H Mohammadzadeh, R Nejad Rahim, A Barazesh, H Taherkhani, Prevalence of Intestinal Parasitic Infections among Mentally Disabled Children and Adults of Urmia, Iran Iranian Journal of Parasitology 2010 5(1):6-19. [Google Scholar]
. B Rajeswary, B Sinniah, H Hasnah, Socio-economic factors associated with intestinal parasite among children living in Gombak, Malaysia Asia Pacific Journal of Public Health 1994 7:21-25. [Google Scholar]
. M Rokni, The present status of human helminthic diseases in Iran Ann Trop Med Parasitol 2008 102(4):283-95. [Google Scholar]
. AS Arani, R Alaghehbandan, L Akhlaghi, M Shahi, AR Lari, Prevalence of intestinal parasites in a population in south of Tehran, Iran Revista do Instituto de Medicina Tropical de Sao Paulo 2008 50(3):145-49. [Google Scholar]
. K Parameshwarappa, C Chandrakanth, B Sunil, The Prevalence of Intestinal Parasitic Infestations and the Evaluation of Different Concentration Techniques of the Stool Examination Journal of Clinical and Diagnostic Research 2012 6(7):1188-91. [Google Scholar]
. M Norhayati, MS Fatmah, S Yusof, AB Edariah, Intestinal parasitic infections in man: a review The Medical journal of Malaysia 2003 58(2):296-305. [Google Scholar]
. M Baghaei, N Pestechian, Z Alav, The prevalence of intestinal parasitic infection among normal and mentally disabled students in Isfahan J Res Med Sci 1999 23(4):62-65. [Google Scholar]
. W Saksirisampant, S Nuchprayoon, V Wiwanitkit, S Yenthakam, A Ampavasiri, Intestinal parasitic infestations among children in an orphanage in Pathum Thani province J Med Assoc Thai 2003 86:263-70. [Google Scholar]
. MA Al-Fellani, AH Khan, RM Al-Gazoui, MK Zaid, MA Al-Ferjani, Prevalence and Clinical Features of Blastocystis hominis Infection among Patients in Sebha, Libya Sultan Qaboos Univ Med J 2007 7(1):35-40. [Google Scholar]
. M Gamboa, J Basualdo, L Kosubsky, E Costas, R Cueto, H Lahitte, Prevalence of intestinal parasitosis within three population groups in La Plata, Argentina European journal of epidemiology 1998 14:55-61. [Google Scholar]
. M Amare, GS Solomon, K Tesfaye, Prevalence of intestinal parasitic infections among urban dwellers in southwest Ethiopia EthiopJ Health Dev 2007 21(1):7-12. [Google Scholar]