meysam sharifdini

Strongyloides stercoralis is one of the neglected tropical diseases. We aimed to verify the genetic diversity of S. stercoralis with attention to clinical features of the infection in patients using the Cox1 gene and DNA sequencing.

Using parasitological methods, S. stercoralis was isolated from stool samples of patients who had been referred to Tehran University of Medical Sciences, Tehran, Iran. The patients originated from three endemic provinces of Iran including Guilan and Mazandaran in the north and Khouzestan in the south of Iran. After recording the clinical symptoms of the patients, DNA extraction of the isolates, PCR, and sequencing of the Cox1 gene region were performed. The gene sequences were analyzed by Chromas, Bio edit, and Dna SP 6.0, and phylogenetic analysis using MEGA 7.

Overall 10 isolates of S. stercoralis were collected from patients 55 to 73 years old. Among the patients, gastrointestinal, respiratory, and cutaneous clinical symptoms were the most common, respectively. Ten isolates were classified into 4 haplotypes, 2 of which were specific to this study. Haplotypes 2 and 3 were placed in a subclade with haplotypes including isolates from dogs in Cambodia. Haplotype 4 which is hereby introduced in the world for the first time included an isolate from a patient with hyper-infection syndrome and disseminated strongyloidiasis.

The Cox1 gene showed genetic diversity for S. stercoralis isolates. Accordingly, no significant genetic difference was observed between the sequences from patients with hyper-infection and non-hyper-infection. The only isolate from a patient with disseminated and hyper-infection strongyloidiasis was genetically different from all other isolates in the present study.

Cystic echinococcosis (CE) is one of the most important neglected diseases and a public health concern worldwide. Due to the poor efficacy of current drugs, novel therapeutic approaches are urgently needed.

This study evaluated the scolicidal effects of the hydroalcoholic extract of Urtica dioica and the chloroformic extract of Pyrus boissieriana on protoscoleces of CE cysts.

Protoscoleces were aseptically aspirated from the livers of sheep naturally infected with CE cysts. To assess the scolicidal effect of these herbal extracts, various concentrations of both extracts (5, 10, 20, 40, and 80 mg/mL) were added to a suspension of 3 × 10 3 washed protoscoleces. After 10, 20, 30, 60, and 120 minutes of exposure, eosin stain was added to each tube, and the viability of protoscoleces was evaluated by flame cell motility under a light microscope, as well as impermeability to 0.1% eosin solution. All experiments were performed in triplicate.

The scolicidal effects of U. dioica extracts at a concentration of 80 mg/mL were 81% and 89% after 60 and 120 minutes of exposure, respectively. Almost the same results were obtained for P. boissieriana extracts at a concentration of 80 mg/mL (81.33% and 89% after 60 and 120 minutes of exposure, respectively), which were significantly different from the negative control group (P < 0.001). However, the extract of U. dioica exhibited stronger scolicidal effects compared to the extract of P. boissieriana at concentrations lower than 40 mg/mL (P < 0.001).

The present findings indicate that both U. dioica and P. boissieriana extracts possess high protoscolicidal activities and could be used as alternative natural medicines in the treatment of CE. However, further studies are required to verify these findings through assessment in animal models and clinical subjects.

This study aimed to determine the distribution of enteric parasitic infections and related risk factors among rural communities of Guilan province, Northern Iran, and to compare the results with the situation in the past.

Intestinal parasitic infections are still considered as a major public health concern, particularly in human communities with poor economy and sanitation.

This cross-sectional study was performed in rural areas of Masal and Shanderman district from February to December 2020. A total of 917 stool samples were collected and examined for presence of intestinal helminthes and protozoa using direct, formalin-ether and Kato-Katz techniques.

 A total of 156 (17%) out of 917 examined individuals were infected with intestinal parasites. The overall prevalence of protozoa, helminths and mixed infections were 11.8% (108/917), 4.5% (41/917) and 0.8% (7/917), respectively. Blastocystis was the most prevalent intestinal protozoa (9.6%) followed by Giardia lamblia (1.9%), Endolimax nana (1.1%), E. coli (0.8%) and Entamoeba hartmani (0.1%). The highest prevalence of intestinal helminths belonged to Trichostongylus spp. (3.5%) and Strongyloides stercoralis (1.3%). Statistical analysis showed significant association between giardiasis and sex (P<0.03). On the other hand, prevalence of enteric helminths was influenced by close contact with livestock, keeping herbivorous animals at home, job, education, and consumption of uncooked vegetables (P<0.05).

The findings indicate a decreasing trend in the prevalence of intestinal parasitic infections in Guilan province in comparison to the past few decades. Hookworm infections, which was very prevalent in the area, are now rare, while trichostrongylosis showed a high prevalence in rural residents of the study area.

Some freshwater snails are as intermediate hosts of human and animal parasitic trematode. Study on freshwater snails’ fauna and cercariae infection play important role to detect sources of infection.

The aim of the present study was to determine diversity and cercariae infection of Lymnaeidae and Physidae freshwater snails and effects of physicochemical parameters of water on their abundance and distribution in Guilan province, North of Iran.

Over one year, a total of 117 regions in Guilan province were investigated for Lymnaeidae and Physidae freshwater snails and identified. Water samples of each region was also collected for physicochemical analyses. Identified snails were examined for cercariae infection by shedding method.

Of 39,486 collected snails, three species of two genera including 19,726 Lymnaea auricularia (49.96%), 4911 L. palustris (12.44%), and 14849 Physa acuta (37.6%) were identified. Cercariae infection rate was 2.36%. Identified cercariae were xiphidiocercariae (0.94%), echinostome (0.8%), furcocercous (0.44%), lophocercous (0.16%), and gymnocephalous (0.02%). The highest infection rate was in spring (3.37%). Temperature and pH had inverse effect and salinity and water electrical conductivity had direct effects on snails’ density.

Two genera of Lymnaea and Physa exist in examined aquatic habitats of Guilan province, North of Iran in different seasons of a year. The physicochemical parameters of water had effects on distribution and snails’ density and also abundance of cercariae infection in them.

Toxoplasmosis is a common parasitic infection with high prevalence and worldwide distribution. It may cause severe disease in the fetus of newly infected pregnant women.

This study aimed to evaluate the seroprevalence of toxoplasmosis and its related risk factors among pregnant women in Ramsar city, Mazandaran province, north of Iran, from October 2017 to March 2018.

In this analytical-cross sectional study, specific anti-Toxoplasma gondii IgG and IgM antibodies were measured in 191 pregnant women by ELISA method. The length of T. gondii infection was estimated by the IgG avidity test. Demographic and behavioral information about pregnant women and possible risk factors of toxoplasmosis were collected through interviews.

Specific IgG antibody against T. gondii was detected in 46.1% and IgM in 5.8% and both IgG and IgM antibodies were detected in 4.7% of pregnant women. The IgG avidity test did not show any acute case of toxoplasmosis. None of the demographic characteristics, such as age, occupation, place of residence, education, income, trimester of pregnancy, frequency of pregnancy, and history of abortion was correlated with toxoplasmosis. Moreover, behavioral characteristics, such as the source of consumed water, contact with soil, presence of cats in the household, consumption of vegetables, type of meat consumed, and the way of cooking meat had no significant correlation with toxoplasmosis seropositivity.

More than half of the pregnant women (54%) were toxoplasmosis-free and therefore at risk of acquiring this infection. Increasing the knowledge of pregnant women about toxoplasmosis prevention may reduce the risk of this infection during pregnancy.

 Toxocariasis is a parasitic disease causing hypereosinophilia. This study aimed to investigate the serological prevalence of toxocariasis among hypereosinophilic children in Children’s Medical Center, Tehran, Iran, as well as to explore its relationship with epidemiological variables and some blood indices.

 This descriptive cross-sectional study was performed in 2020 on children referred to referral children hospital for routine tests. A total of 282 children diagnosed with hypereosinophilia were selected and included in the study, and then, their serum was collected. After obtaining informed consent from their parents, the parents were asked to fill out a questionnaire. The serological ELISA test was used to assess the anti-Toxocara IgG antibody. Data were analyzed using SPSS software 18.

 Out of 282 hypereosinophilic children, 17 (6%) had serological results positive for anti-Toxocara antibody. The mean age of children with toxocariasis was higher than that of children without toxocariasis (P = 0.312). Furthermore, ESR and CRP variables were significantly higher in infected children than those in non-infected children (P < 0.05).

 The results of the present study confirmed the relationship between toxocariasis and hypereosinophilia. Since the symptoms of toxocariasis are non-specific and may go undiagnosed, it was found necessary to examine toxocariasis in cases of hypereosinophilic individuals.

We report a case of Hymenolepis diminuta infection in a two years old boy living in Guilan Province, northern Iran diagnosed in 2019. The patient was complained of anorexia, weight loss, weakness and disturbed sleep. Stool examination revealed numerous eggs of H. diminuta. After treatment with a single dose of oral praziquantel, the patient recovered without evidence of the egg shedding in follow-up stool samples. Moreover, we performed detailed phylogenetic analysis of the H. diminuta comparing with other isolates deposited in GenBank database based on Cox1 gene. Based on BLAST analysis of Cox1 gene our sequence showed 97.4-99.2% similarity with those of H. diminuta available in GenBank. The present study recommends the importance of reporting the infection cases, in order to improve knowledge on epidemiology and control of the neglected disease.

The raccoon, Procyon lotor, is native to North and Central America but has been introduced to several Old World countries including Iran. The aim of this study was to determine the prevalence of ectoparasites of raccoons in Iran. During 2015–2017, a total of 30 feral raccoons were collected from Guilan Province, northern Iran. The fur of raccoons was examined for the presence of ectoparasites. The collected ectoparasites were preserved in 70% ethanol and microscopically and morphologically identified. In total, 11 fleas and 244 ixodid ticks were collected from 18 (60%) raccoons for the first time in Iran. Two raccoons (6.7%) harbored just fleas, five raccoons (16.7%) both fleas and ticks and 11 raccoons (36.7%) just ticks. Two species of fleas: Ctenocephalides felis (cat flea) and Pulex irritans (human flea) were collected from seven raccoons (23.3%). Four species of ixodid ticks: Haemaphysalis concinna, Ixodes ricinus, Rhipicephalus sanguineus and R. turanicus were collected from 16 raccoons (53.3%). All ectoparasites, except for cat flea, were found on raccoons for the first time. The prevalence, mean abundance and mean intensity of ectoparasites and the indices of affinity, association and diversity were calculated. The pair of species H. concinna/I. ricinus showed significant association and the infestation with I. ricinus in cubs was significantly higher than in adults (P ˂ 0.05). The medical importance of zoonotic infections transmittable by raccoons and their ectoparasites is discussed. The investigation of different possible vector-borne infections in raccoons and their ectoparasites in the study area is suggested.

The raccoon, Procyon lotor Linn. (Procyonidae) is native to North and Central America but has been introduced in several European and Asian countries including Japan, Germany and Iran. Objective of this study was to determine frequency of gastrointestinal and tissue helminthes from feral raccoons in Iran.

During 2015-2017, 30 feral raccoons including 12 males and 18 females were collected from Guilan Province, northern Iran (the only region in Iran where raccoons are found). The gastrointestinal tracts and tissues such as lung, liver and muscles were examined for presence of helminthes.

Twenty raccoons (66.7%) were found infected with five intestinal helminth species. The prevalence of infection with Strongyloides procyonis Little, 1966 (Nematoda) was 63.3%, Plagiorchis koreanus Ogata, 1938 (Trematoda) (13.3%), Centrorhynchus sp. Lühe, 1911 (Acanthocephala) (10.0%), Camerostrongylus didelphis Wolfgang, 1951 (Nematoda) (3.3%), and Spirocerca lupi Rudolphi, 1809 (Nematoda) (3.3%). No larvae or adult worms were found in other tissues of the examined raccoons.

Most of the raccoons were infected with S. procyonis. The public health importance of zoonotic parasites transmittable through raccoons, the rapid control and decrease of raccoon populations and their distribution in Iran are also discussed.

Strongyloidiasis is caused by intestinal nematode called Strongyloides stercoralis (S. stercoralis) which can lead to hyperinfection syndrome and disseminated infections. If not diagnosed and properly treated, it can even lead to death. The sensitivity of parasitological methods is not high enough and multiple stool sampling over consecutive days is essential to improve the detection rate. The agar plate culture method is more sensitive to the detection of S. stercoralis in fecal samples than other parasitological techniques. Serological tests have demonstrated higher sensitivity, but they have low specificity because of cross-reactivity with other helminthes. Moreover, they are not helpful for follow-up of treatment, because they cannot distinguish between new and old infections. Recently, some Polymerase Chain Reaction (PCR)-based techniques have been developed for detection of S. stercoralis with high sensitivity and specificity. These methods are rapid but expensive and need well-equipped laboratories. In this paper, conventional and novel methods for laboratory diagnosis of strongyloidiasis are reviewed.

Intestinal parasitic infections (IPIs) are among the most important etiologies of gastrointestinal disorders in developing countries. The present study was performed to determine the prevalence of IPIs in rural inhabitants of Fouman, northern Iran.

Overall, 31 villages were randomly selected during 2015-2016. Stool samples were collected from 1500 inhabitants aged 2-87. The samples were examined by direct wet smear, formalin ethyl-acetate concentration and agar plate culture. Trichrome staining and modified acid-fast staining were used as confirmatory tests for intestinal amoeba and flagellates and cryptosporidium spp., respectively. Data were analyzed with Chi-Square and Fisher exact tests using SPSS.

8.06% of participants were positive for at least one intestinal parasite. The prevalence of mixed parasitic infections was 0.87%. The most prevalent IPIs were caused by Trichostrongylus spp. (3.13%), followed by Strongyloides stercoralis (1.5%), Giardia lamblia (1.3%), and Entamoeba coli (1.0%), Blastocystis hominis (0.86%), E. histolytica/dispar (0.53%), Endolimax nana (0.26%), Iodamoeba butschlii (0.13%), Trichuris trichiura (0.07%), Enterobius vermicularis (0.07%), Hook worm (0.07%) and E. hartmani (0.07%). Statistically, the prevalence of IPIs showed significant differences regarding the age groups, education status, occupation (P<0.001), and the habit of eating raw vegetables (P<0.007), whereas, the differences were insignificant with regard to sex (P=0.924) and water supply (P=0.088).

The prevalence of IPIs, especially soil-transmitted helminthes (STHs) has sharply decreased in northern Iran. Excluding Trichostrongylus spp. and S. stercoralis, other intestinal parasites only produce a marginal and unnoticeable health problem in this area, today.

Echinococcus granulosus parasite causes a zoonotic disease which is important for public and veterinary health. Since pumpkin seeds (Cucurbita sp.) are used as traditional vermifuge in Iran, they may be a potential herbal anthelmintic.

This study was designed in 2016 to evaluate the in vitro scolicidal effect of Cucurbita moschata seeds form northern part of Iran. Hydroalcoholic and petroleum ether extracts were prepared by maceration and soxhlet respectively. Both extracts with four different concentrations (100, 10, 1, 0.1 mg/ml) were incubated against protoscoleces in 5, 15, 30 and 60 min.

Maximum mortality was 16% with 1% hydroalcoholic extract in 60 min. The highest mortality with organic extract was 4% with 10% concentration in 60 min (P=0.015).

Since highest mortality was 16%, the extract did not reach to LD50 (50% mortality). Therefore, the potency of the total extract is not sufficient as potential scolicidal drug.

We report a human case of Hymenolepis diminuta infection in Guilan Province, northern part of Iran in 2017. The patient was a 15-month-old boy with gastrointestinal symptoms. In stool examination, eggs of H. diminuta was found based on morphological characteristic. The infant was successfully treated with a single oral dose of praziquantel, and then completely recovered. For the first time, we report human infection with this species in north of Iran.

We detected eight trematodes in the small intestine of a road-killed jackal (Canis aureus) from Hamidiyeh District near the city of Ahvaz, Khuzestan Province in 2010. Three worms were stained with carmine acid, mounted in Canada balsam on glass slides and examined under a light microscope at 1000X magnification. PCR and sequencing of a partial ITS2 sequence were used to approve the diagnosis. The flukes measured ≈1 mm in length with an elongated ovoid shape resembling the members of heterophyid, and only one testis, characteristics of the genus Haplorchis. Sequencing of a 481-bp fragment of the ITS2 locus from the worms revealed 97%-98% identity with the similar sequences of the H. taichui flukes previously identified in the fish, cat, and humans from Thailand, China, and Vietnam. Further studies with the application of reliable molecular tools to diagnose trematode infections in wildlife and humans can bring more insight into the epidemiology of fish-borne flukes including H. taichui in this area.

Trichostrongylus spp. are common parasites of herbivorous animals and trichostrongyliasis is an important zoonotic disease in Iran, especially in northern Iran. Routine laboratory methods for diagnosis of these infections are direct smear and formalin-ethyl acetate techniques. There is no enough evidence about the sensitivity of nutrient agar plate culture for detection of Trichostrongylus spp infections. The objective of this study was to compare the nutrient agar plate culture and the formalin-ethyl acetate sedimentation techniques for laboratory diagnosis of human trichostrongyliasis in an endemic area of northern Iran. A total of 1553 fresh stool samples were collected from residents of 31 villages within the Fouman district in Guilan province during 2015–2016. All samples were examined using nutrient agar plate culture and formalin- ethyl acetate concentration techniques for detection of Trichostrongylus spp. infections. Overall, 71 cases were diagnosed with Trichostrongylus spp. by at least one of the methods. Considering parasitological results as the diagnostic gold standard, the sensitivity and specificity of nutrient agar plate culture were 90.1% and 100%, respectively. Also, the sensitivity and specificity of the formalin ethyl acetate concentration method were 95.8% and 100%, respectively. According to the results of this study, the formalin ethyl acetate method is more sensitive than nutrient agar plate culture in the diagnosis of human trichostrongyliasis, especially in humid climate regions such as North of Iran.

The aim of the present study was to simultaneously investigate parasitic contamination of treated wastewater and downstream
vegetable farms that are irrigated with treated sewage, during a year. (Oo) Cysts and eggs of parasites are resistant to most of routine wastewater treatment process. Irrigation of vegetables
farms with either treated wastewater or illegally use of raw wastewaters enhances the risk of contamination with enteric pathogens. The treated wastewater samples were taken after chlorination from a wastewater treatment plant located at the south of
Tehran. In addition, 60 vegetable samples (5 samples from each farm) were collected from the selected downstream farms that
routinely used treated wastewater for irrigation of crops. Parasitological tests were performed using Ziehl–Neelsen, conventional
lugol’s iodine staining and direct microscopical examination. Parasites including free living larvae, eggs of Toxoascaris leonina, egg of Toxocara sp. Trichuris sp, Trichostrongylus sp
and amoeboid trophozoite were seen in 5/12 (41.7%) of vegetable samples gathered during a year. There was no statistically
significant correlation between the season and parasitic contamination of the vegetables (P= 1). Furthermore, parasitic contamination
was observed in 7/12 (53.8%) of treated wastewater samples. The correlation between season and parasitic contamination of treated
wastewater was evaluated that the results showed a higher contamination of treated wastewater in spring and autumn (P<0.05).
Fisher’s exact test also showed that there was no significant correlation between parasitic contaminations of vegetable samples and
treated wastewater according to seasonal change. The results showed parasites in both treated wastewater plant and downstream crops farms that suggests the public
health importance of the quality of water resources that routinely used for irrigation of vegetable farms

Aim: This study is aimed to diagnose and analyze strongyloidiasis in a population of an endemic area of Iran using nested-PCR, coupled with parasitological methods.
Screening of strongyloidiasis infected people using reliable diagnostic techniques are essential to decrease the mortality and morbidity associated with this infection. Molecular methods have been proved to be highly sensitive and specific for detection of Strongyloides stercoralis in stool samples.
A total of 155 fresh single stool samples were randomly collected from residents of north and northwest of Khouzestan Province, Iran. All samples were examined by parasitological methods including formalin-ether concentration and nutrient agar plate culture, and molecular method of nested-PCR. Infections with S. stercoralis were analyzed according to demographic criteria.
Based on the results of nested-PCR method 15 cases (9.7%) were strongyloidiasis positive. Nested-PCR was more sensitive than parasitological techniques on single stool sampling. Elderly was the most important population index for higher infectivity with S. stercoralis.
In endemic areas of S. stercoralis, old age should be considered as one of the most important risk factors of infection, especially among the immunosuppressed individuals.

Hookworm infection is one of the important Neglected Tropical Diseases (NTD) in the world. It was previously more prevalent in the northern and southern parts of Iran with a prevalence rate higher than 40% in some endemic regions; nevertheless, the infection rate has decreased to less than 1%. This study aimed to determine prevalence and molecular aspects of hookworm infections in rural inhabitants of Fouman County, Guilan Province, northern Iran
This cross-sectional study was performed in 31 villages of Fouman district in Guilan Province, northern Iran during 2015-2016. Stool samples were collected from 1500 rural inhabitants and examined by formalin ethyl-acetate concentration as well as agar plate culture techniques. After treatment with albendazole, adult hookworms were isolated. FollowingDNA extraction,PCR amplification of ITS2-rDNA region was performed and the product was sequenced, followed by genetic variation analysis.
Of 1500 samples, one case was morphologically diagnosed as N. americanus. In addition, molecular characterization verified the presence of N. americanus, showing more than 95% similarity with sequences of N. americanus present in GenBank. The patient showed no clinical symptoms and a mild hypereosinophilia was the only laboratory finding observed.
A reduced prevalence of human hookworms was demonstrated within Guilan Province located in north of Iran. The N. americanus originated from Guilan had a high homology with the isolates found in Japan, Laos, Malaysia, and Australia.

Carnivore carcasses on the roads can be regarded as study materials in parasitology and eco-epidemiology. Stray carnivores such as dogs and cats are known to harbor so many different pathogens like zoonotic helminthes. The current investigation, apparent the status of the helminthic parasites found in road killed carnivores from different parts of Guilan Province north of Iran.
Fifty road killed carnivores including 27 stray dogs (Canis familiaris), 11 golden jackals (Canis aureus) and 12 stray cats (Felis catus) were collected from 21 locations of Guilan Province, during Apr to Nov 2015. Internal organs of the carcasses, including digestive tract, heart, kidneys, lungs, liver, skin, eyes as well as muscles were carefully inspected and sampled for helminthological investigation.
About 80% of the 50 carnivores, (stray dogs 77.77%, golden jackals 81.81%, and stray cats 91.66%) were found naturally infected with helminthic parasites. Dipylidum caninum, Toxocara cati, Toxocara canis, Toxascaris leonine, Ancylostoma caninum, Ancylostoma tubaeforme, Dirofilaria immitis, Dioctophyma renale, Dipylidum caninum, Echinococcus granulosus, Mesocestoides spp., Taenia hydatigena, Taenia hydatigera, Joyuxiella spp., Spirometra spp. are reported herein.
The prevalent occurrence of zoonotic helminthes such as T. canis, T. cati, T. leonina, E. granulosus, D. immitis and D. renale in stray carnivores should be considered as a public health hazard, specifically within a vast tourism area like Guilan Province.

Dirofilaria immitis is an important filarial nematode in dogs. In this study, age and sex distribution of this zoonotic nematode among dogs were investigated in northwest of Iran in Meshkin-Shahr city. Molecular characteristics of the isolates, based on cytochrome oxidase subunit 1 (COX1) gene were compared to the isolates from other areas of the world.Blood samples were collected from 91 dogs which were selected by simple classified accidental sampling. Thin and thick blood smear examinations were used to find out infectivity with D. immitis. DNA extraction was performed from adult D. immitis recovered from heart of infected dogs. The COX1 gene was amplified and sequenced. Phylogenetic analysis was carried out using sequences obtained in this study along with relevant sequences deposited in the GenBank. Phylogenetic analysis and sequence variation was performed using MEGA software in comparison with those COX1 sequences deposited in GenBank. Out of 91 dogs, 19 (20.87%) were found positive for infection with D. immitis. There was no statistically significant difference between males and females of dogs in terms of D. immitis infection. However, the rate of infection in dogs more than 2 years old was significantly higher than those with lower age. Both sequences analyzed in this study showed 100% homology to each other. Intra-species variation of these isolates with those from other areas of the world amounted to 0 to 0.50%. Phylogenetic analysis of the COX1 gene suggested that it is conserved, and can be used for study on genetic diversity and classification of filarial nematodes.

As far as no study has been done on the prevalence of parasitic infections in Saveh, Markazi Province, Iran, the current study aimed to investigate the prevalence of intestinal parasitic infections in rural areas of Saveh during 2005-2006. 755 people were selected and examined randomly through systematic cluster sampling for intestinal parasites using formalin ether sedimentation technique, as well as direct smear for the diarrheic samples. In general, 14% of individuals were infected with intestinal parasites. The rate of infection with protozoa and helminth parasites were 13.3% and 0.7%, respectively. The infection rate of each parasite species were as follows: Entamoeba coli 5.9%, Giardia lamblia 5.6%, Blastocystis hominis 1.6%, Iodamoeba butchli 0.1%, Chilomastix mesnili 0.1%, Hymenolepis nana 0.3%, Enterobius vermicularis 0.3% and Taenia 0.1%. Comparing the prevalence of intestinal parasites in other parts of the country, especially the rural areas, it is found that the prevalence was lower in Saveh, which is prominent for helminthes parasites. Considering that Saveh is known as a healthy city, the efficient health services in this area is concluded from the obtained results. Therefore, providing treated safe water and sanitation for the reduction of parasites, especially Giardia are recommended in the study area.

Clinical manifestations of Strongyloides stercoralis are variable from asymptomatic to hyperinfection and devastating disseminated infections. Hereby, clinical characteristics of a large series of Iranian strongyloidiasis indigenous cases are described. The records of people referred to the Helminthological Diagnostic Labora­tory of School of Public Health, Tehran University of Medical Sciences and School of Medicine, Gilan University of Medical Sciences, during 2009-2013 were reviewed. For those patients that were infected with S. stercoralis and their clinical manifestations and demographic data were available (70 cases) a checklist was pre­pared and data analyzed. Forty-three patients (61.4%) were male and 27 (38.6%) female. Gastrointesti­nal, cutaneous and pulmonary symptoms were present in 71.4%, 25.7%, and 15.7% of patients, respectively. None of them had larva currens erup­tion. Eosinophilia was the most prevalent reason for suspicious on S. stercoralis, but the mean was lower in elderly patients. Hyperinfection were recorded in 8 patients (11.4%), and 2 cases had disseminated infection. Eosinophilia is common both in asymptomatic and symptomatic cases of strongyloidiasis, but the mean tend to lower with increase in age.

Lymphatic filariasis (LF), a nematode disease transmitted by arthropod vectors, is repeatedly reported in immigrant population. This disease is not endemic in Iran; however, different species of mosquitoes, capable of transmission of parasite microfi­laria, are distributed in the country. Hereby, incidental detection of an im­ported case of LF due to Wuchereria bancrofti in an Indian worker in Iran is reported. Identification of the case was performed based on morphological and morphomet­rical characteristics of microfilaria and PCR sequencing.

Acanthamoeba genus is introduced as opportunistic and cosmopoli­tan parasite. Monkey and wistar rat are appropriate models for experimental study on Acanthamoeba infection. In this study Acanthamoeba spp. were isolated from hot spring (HS), windows dust (WD) and a corneal sample of keratitis patient (KP) and their pathogenicity surveyed by in vitro and in vivo tests. Isolates of Acanthamoeba were cultivated axenically for 12 months in PYG medium. Overall, 30 wistar rats, in 6 equal groups were used for developing experimental Acanthamoeba keratitis (AK) and Granulomatous Amoebic Encephalitis (GAE). The Keratitis and Granulomatous Encephalitis experiments were per­formed by intrastromal and intranasal inoculation of Acanthamoeba cysts, respec­tively. Pathogenicity of the three isolates was also evaluated by in vitro test using osmotolerance and temperature tolerance assays. Identification of genotypes were performed by PCR technique and sequencing. None of the isolates could perform AK and GAE in wistar rats, although all isolates were described as T4 genotype. Isolates obtained from KP and WD could grow only in 30 °C, but not in 37 °C and 40 °C. On the other hand, HS iso­late grew in 30 °C and 37 °C but not in 40 °C. Moreover, all of isolate grew in 0.5 M mannitol but not in 1 M and 1.5 M. T4 isolates with a long-term axenic culture and different factors re­lated to host and parasite may play role in pathogenicity of these free-living amoe­bae.