mostafa rezaeian

Trichomoniasis is a common sexually transmitted infection (STI) caused by the protozoan Trichomonas vaginalis, which causes health and emotional damages to the sufferers annually. We aimed to investigate the prevalence of T. vaginalis and its related risk factors among the high-risk women in the city of Karaj, central Iran.

This cross-sectional study was conducted between October 2021 and September 2022. In all 192 samples were taken from high-risk women referred to the center for vulnerable women and also from women in Fardis Prison of Karaj. All samples were examined by culture and microscopic method.

The overall prevalence of T. vaginalis in high-risk women was estimated at 7.8% (15/192). Subgroup prevalence was also assessed according to the severity of symptoms, and no significant association was observed between the prevalence and the symptoms’ severity.

Due to the high prevalence of the parasite among vulnerable/high-risk women, particularly in people with poor socioeconomic conditions, preventive health measures in this high-risk group seem necessary. Nevertheless, given that men have no symptoms but may be carriers of the parasite, the same study is also recommended for men.

The aim of this research was to compare excretory-secretory and somatic extract materials of Fasciola hepatica and F. gigantica to detect protein maps of two species.

Twenty infected livers were collected from sheep in industrial slaughterhouse in Tehran, 2017-2019. Worms were detached from bile ducts, then recognized according to morphologic and morphometric criteria. After three times washing, worms were incubated in RPMI culture media and excretory-secretory products were collected. Worms were crushed and homogenized for preparation of somatic extract. Two Dimensional Electrophoresis gels were accomplished for both excretory-secretory material and somatic extracts. Gels were scanned with densitometer and analyzed with Same Spots software and protein spots were identified with Expasy database.

For both excretory-secretory products and somatic extract, protein spots were appeared with two-dimensional electrophoresis technique. Quantitative analysis showed 40 and 28 protein spots for excretory-secretory of F. hepatica and F. gigantica respectively. For somatic extract 19 and 12 protein spots were recognized for F. hepatica and F. gigantica in that order.

The rate of expression of some proteins were more in F. hepatica while expression of other proteins was high in F. gigantica. The expression of protease enzyme was higher in F. gigantica than F. hepatica. These data could be considered for biochemical differentiation of Fasciola species and subsequently to design and prepare of antigens for diagnosis/vaccine development.

In this study, some microsporidial and coccidian parasites were isolated from 103 domestic cats in the Meshkin Shahr area, northwestern Iran during the Jun 2014 to Jun 2015, and their genera were identified using parasitological methods with emphasis on their zoonotic importance. One hundred and three fecal samples of domestic cats were collected and preserved in formalin (10%) and conserved in phosphate buffer saline solution, finally examined by microscopy after formalin-ether concentration and specific staining. Preservation in dichromate potassium (2.5%) was performed for all coccidian positive samples and then sporulated coccidian oocysts were investigated. The detected parasites were Isospora spp. 6/103(5.8%). Microsporidian spores were identified in 46/103 (44.6%) of all samples post-stained by the aniline blue staining method. Microsporidial infections were more prevalent in domestic cats. Further studies are needed in the identification of microsporidial spores isolated from infected cats.

Microsporidia as one of the most important pathogens in veterinary and agricultural settings, have emerged in immunocompromised patients in Iran. To date, different Enterocytozoon bieneusi genotypes have been identified in humans and animals, supporting the possibility of zoonotic zoonosis transmission potential. The aim of this study was to evaluate the distribution of E. bieneusi genotypes among overpopulated stray dogs in vicinity of Tehran, the capital city of Iran. Totally, 75 stool and 75 urine samples were obtained from 75 stray dogs during the time period from Mar 2015 to Oct 2015. DNA extraction was performed on all the samples and specific fragment of small subunit ribosomal RNA gene of E. bieneusi and Encephalitozoon spp. was amplified. Furthermore, specific primers targeting the internal transcribed spacer region of E. bieneusi were applied to determine the genotype of the microorganism. Microsporidia was detected in 5.3% of stool samples, while none of the urine samples was positive for microsporidia species. Overall, 440 bp fragment of E. bieneusi was amplified in all the samples and there was no amplification for Encephalitozoon spp. The results of sequencing of 410 bp fragment of internal transcribed spacer region showed that all the E. bieneusi were genotype D. E. bieneusi was the most prevalent microsporidian species in the stray dogs and all the positive isolates were characterized as genotype D.

This study aimed to investigate the anti-Acanthamoeba effects of the most used marketed disinfecting solutions in Iran. Moreover, the efficacy of some nano-compounds was tested against pathogenic Acanthamoeba.
The present study was conducted in the School of Public Health, Tehran University of Medical sciences, Tehran, Iran during 2015-2016. Cysts of Acanthamoeba T4 genotype (7 x 104 /ml) mixed at the equal volume with contact lens solutions including Opti-free, Ginza, ReNu, Maxima, Light, and Cyclean for the recommended time by the manufacturers. Nano-silver and nano-gold compounds were also treated with the amoebae. Chlorhexidine 0.02% and normal saline were used as positive and negative controls, respectively. Dead and alive amoebae were determined using vital stain and suspension was cultured in non-nutrient agar. The entire process was repeated at least three times.
In none of the solutions in the manufacturer's brochure recommended time, full cytotoxic effect was observed on the cysts of Acanthamoeba. Opti free express solution destroyed the cysts after 6 days. Nanosilver and nano-gold compounds showed no cytotoxic effect on the cysts of Acanthamoeba.
None of the Nanoparticles compounds as well as contact lenses disinfecting solutions which studied was effective on Acanthamoeba cysts in the manufacturer's brochure recommended time. However, continuing study on Nano-silver and Nano-gold compounds to find effective ingredients against Acanthamoeba are highly recommended.

Blastocystis is the most common anaerobic protozoa living in the large intestine of a broad spectrum of vertebrates.
The aim of this study was to investigate the Blastocystis infection rate in inflammatory bowel disease (IBD) patients.
A total of 80 stool samples were collected from IBD-proved patients. All stool samples were cultivated in Dulbecco’s modified Eagle’s medium and checked by light microscopy for detection of Blastocystis. The Correlation between demographic data of IBD patients and Blastocystis was calculated using SPSS 23.
The enrolled patients comprised of 52 (65%) men and 28 (35%) women. The study showed Blastocystis in 16/80 (20%) of the samples by microscopic examination and culture method. The parasite was seen among 12 (23.08%) and 4 (14.29%) men and women, respectively. No statistically significant correlation was found between infection with the parasite and animal contact. Fisher’s exact test represented that there was no correlation between gender and the presence of Blastocystis (p value= 0.397). Fisher’s exact test denoted that there was no statistical correlation between age and the presence of the parasite (p value= 0.130).
In this study, Blastocystis was found in 20% of enrolled patients who suffered from IBD. This infection rate was significantly higher than the studies have previously described Blastocystis in this group of patients.

Trichomonas muris is one of the most common protozoa diagnosed in rodents. The trichomonads are generally described as presenting only trophozoite form while pseudocyst is another morphological form of trichomonads identified among gastrointestinal and genitourinary trichomonads. We identified and described different shapes of T. muris pseudocysts and trophozoite in stool samples were collected from rodents including Merinos persicus, Mus musculus and Cricetulus migratorius.
In this cross-sectional study, stool samples from 204 trapped rodents were collected from Meshkin Shahr during Mar to Dec 2014. Samples were preserved in formalin 10% and PVA solution and transferred to Department of Medical Protozoology and Mycology, School of Public Health, Tehran University of Medical Sciences. Formalin-ether concentration method was used for the samples. The slides were stained with trichrome staining method and observed under light microscope.
The trophozoites were classified as T. muris based on size (18 to 24 µm), presence of three anterior flagella, recurrent flagellum, undulating membrane, and axostyle in direct examination and stained slides with trichrome staining method. Fifty-five out of 204 (27%) rodents were infected with T. muris in which 51(25%) samples pseudocysts form were observed. The spherical bodies of pseudocyst with almost 8 µm size, contained internalized flagella, an undulating membrane with recurrent flagellum, axostyle, and costa were seen. The pseudocysts were more prevalent than trophozoite form and pseudocysts were found with different shapes in this study.
T. muris pseudocysts were found in stool samples of caught rodents for the first time in northwestern Iran.

Diarrheal disease annually causes 760000 deaths in children, and 1700 million new cases are reported each year worldwide. Among the parasites, Entamoeba histolytica, Giardia intestinalis, and Cryptosporidium spp. are the most important infectious agents leading to diarrhea. Clinical presentations due to these parasites are more or less similar, and microscopy is not as much as sensitive for the detection. The aim of this study was to set up and evaluate a Multiplex PCR Assay for Synchronous Identification of Entamoeba histolytica, Giardia intestinalis, and Cryptosporidium spp. in Stool Samples
Samples were obtained from different sources such as culture media and patient stool samples. Primer pairs were designed using primer-BLAST, and for the extraction of DNA, the QIAamp DNA stool mini kit was used. The study was conducted in Tehran, Iran and completed in 2016.
The current multiplex PCR assay for the detection of E. histolytica achieved sensitivity and specificity of 86.36% (95% CI: 65.09% to 97.09) and 95.74 % (95% CI: 85.46% to 99.48%), respectively. Sensitivity and specificity of the test for G. intestinalis was 90.91% (95% CI: 70.84% to 98.88%) and 95.74% (95%CI: 85.46% to 99.48%), respectively, and for the detection of Cryptosporidium, multiplex PCR showed a sensitivity of 90.91% (95% CI: 70.84% to 98.88%) and specificity of 95.74% (95%CI: 85.46% to 99.48%).
Multiplex PCR in this study showed admissible sensitivity and specificity for the detection of E. histolytica, G. intestinalis, and Cryptosporidium spp. in fecal samples.

This study aimed to estimate the prevalence of trichomoniasis infection among females in Tehran, Iran.
This study was conducted on 482 women referred to the 6 obstetrics and gynecology centers of Tehran during 2015-2016. Some information including education, occupation, and number of sexual partners was obtained and clinical signs and symptoms of the genital tract were diagnosed by clinical examination. Two swabs were collected from the posterior fornix of patients. Two laboratory techniques, wet mount, and culture were carried out. Finally, statistical analysis test was performed using SPSS software version 16.0.
Age distribution of patients was 15-60 yr. Trichomonas vaginalis was detected in 2 out of 482 participants (0.41%). All of the infected individuals were married (0.43%) and they had unique sexual partner and all of them had clinical symptoms. Significant association was observed between incidence of T. vaginalis infection and educational levels (P= 0.03), occupation (P=0.006), clinical symptoms (P=0.001), marriage (P=0.006) and bacterial infection (P=0.018).
The prevalence of trichomoniasis was low and its incidence was associated with several risk factors.

Microsporidia have been reported as the cause of opportunistic infections in immunocompromised patients in Iran and other countries. There is no data on prevalence of intestinal microsporidia in healthy population of Iran. This study aimed to provide preliminary data on the present status of microsporidia infection in the local healthy population in Jiroft, Kerman Province from southeastern Iran in 2013-2014.
Fresh stool samples were randomly collected from 418 residents in rural 209 (50%) and urban 209 (50%) areas of Jiroft. All of the collected samples were concentrated with conventional formalin-ether, stained with Ryan blue. Microscopic examination was performed with high magnification on each sample separately for the demonstration of microsporidia spores.
Microsporidial spores were identified in 41 out of 418 (9.8%) samples including 16.41(39%) from rural areas and 25.41(61%) from urban areas. In general, there was no significant difference between sex, age, job, education, and contact with soil and livestock, water supply, gastrointestinal disorders and microsporidia infection among general population in Jiroft.
Intestinal microsporidia infection without clinical manifestations is prevalent in general population resident in southeastern Iran. Appropriate molecular methods are needed for microsporidia species identification.

Acanthamoeba spp. is potentially pathogenic free-living amoeba that can exist in various water sources. The presence of this amoeba in water sources could be a health hazard as Acanthamoeba could lead to severe diseases such as Acanthamoeba keratitis and encephalitis. This study aimed to determine the genotypes of isolated Acanthamoeba spp. in raw wastewater samples in Tehran, Iran.
Overall, 90 raw wastewater samples were collected from water treatment facilities in west and south of Tehran, Iran during 2014-2016. Water samples were filtered and cultured on non-nutrient agar (NNA) medium enriched with Escherichia coli. Morphological and molecular analyses were done on positive strains. The pathogenic ability of the isolated strains was determined using physical assays.
Totally, 6 out of 90 (6.7%) samples were positive for Acanthamoeba, according to morphological characteristics of double-walled cysts. Genotyping and sequencing of the positive strains showed Acanthamoeba belonging to T4 (83%) and T11 (17%) genotypes. In vitro pathogenicity tests were revealed that five isolates were classified as non-pathogenic strains and one strain belonging to T4 genotype was classified as the highly pathogenic amoebae.
The current research reflected a low contamination of wastewater sources to Acanthamoeba. More studies regarding the contamination of wastewaters before and after treatment are required in different places of the country.

Majority of parasitic infections in rodents have zoonotic importance. This study aimed to determine the frequency and intensity of intestinal protozoa infections of rodents including Meriones persicus, Mus musculus and, Cricetulus migratorius.
This survey was conducted in Meshkin Shahr district in northwestern Iran from Mar. to Dec. of 2014. Intestinal samples of 204 rodents including M. persicus (n=117), M. musculus (n=63) and C. migratorius (n=24) were parasitologically examined. Formalin-ether concentration method was done for all of rodents stool samples and observed with light microscope. All of suspected cases were stained with trichorome staining Method. Cultivation in dichromate potassium 2.5% was carried out for all of coccidian positive samples. Acid fast and aniline blue staining methods were used for detecting of coccidian oocysts and intestinal microsporidial spores, respectively.
About 121(59.3%) of the caught rodents were generally infected with intestinal protozoa. Entamoeba muris 14(6.9%), Trichomonas muris 55(27.0%), Chilomastix betencourtti 17 (8.3%), Giardia muris 19(9.3%), Eimeria spp. 46(22.5%), Isospora spp. 4(2%) and Cryptosporidium spp. 1(0.5%) were found from the collected rodents. Microsporidian spores were identified in 63 (31%) out of the 204 collected rodents using aniline blue staining method.
Since some of the infections are zoonotic importance thus, control of rodents can be decreased new cases of the parasitic zoonoses in humans.

Amebiasis with up to 100 000 human deaths each year is the third cause of human deadly parasitic disease. With regard to the fact that cysteine protease 5 is known to be one of the most important pathogenicity factors of the Entamoeba histolytica and also, CP5 gene has been observed only in E. histolytica, hence we discriminated E. histolytica from E. dispar on CP5 gene by polymerase chain reaction (PCR) and characterized CP5 gene variation in E. histolytica isolated from patients in both cold regions and tropical regions of Iran at molecular level.
In the present study, a total of 2332 stool samples (1550 from Tabriz and 782 from Bandar Abbas) were studied microscopically. DNA extraction and PCR method were performed on the positive specimens, infected with E. histolytica/E. dispar. Finally we characterized CP5 gene in E. histolytica isolates from 10 positive samples in the cold regions (Tabriz) and 10 positive samples in the tropical regions (Bandar Abbas) by sequencing and studied the polymorphism of the gene.
Of 1550 subjects studied from Tabriz and 782 from Bandar Abaas, 83/1550 (8.3%) and 65/782 (5.35%) persons were infected with E. histolytica/E. dispar, respectively. The molecular results on 20 E. histolytica PCR positive isolates from both regions revealed that nucleotides substitution and polymorphism on CP5 gene was more in samples from Bandar Abbas than those from Tabriz.
Prevalence of amebiasis was high in the tropical region (Bandar Abbas) compared with the cold region (Tabriz). In this study, CP5 gene variation in the pathogenicity and virulence of this parasite in the tropical region was higher than that in the cold region.

Along with the newly emergence of paleoparasitology research in Iran, findings of parasites from Northern part of the county have not been reported so far. In this study tracking for the lancet liver fluke dates back 250 BC is addressed.
Samples were taken from grave crypts of the soil layers attached to the pelvic bones from above-mentioned site in 2015. The laboratory examinations were conducted in the Dept. of Medial Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Current rehydration technique using TSP 0.5% was utilized for examining the samples.
Out of 10 burial soil samples examined, one individual was seen parasitized with a Dicrocoelium egg. The burial belonged to an adolescent male 20-22 yr old. The egg was in brown color and the length/width parameters of 36×22/5 µm. Parthian coins found in nearby the burials in Kiasar Cemetery, declared the time of the skeleton about 247 BC – 224 AD confidently.
Although the possibility of transit infection with D. dendriticum is high, yet the environmental and geographical conditions in that time are in favor of a normal human transmission in northern Iran.

Blastocystis is one of the most common parasites, reported from both human and animals. This parasite is more prevalent in regions with low levels of hygiene, close contact with animal and unsuitable disposal systems. The aim of the study was to subtype Blastocystis sp., isolated from diarrheic and non-diarrheic patients using sequencing of 18S ribosomal DNA.
Totally, 300 stool samples were collected from diarrheic and non-diarrheic patients referred to Imam Reza Hospital, Tehran from Apr to Aug 2015. All samples were concentrated using conventional Formalin – ether technique and recognized under light microscope. The fresh stool samples were also cultivated in clotted fetal bovine medium and examined for growing of Blastocystis every 48 h with direct smear slides for 10 d.DNA extraction was performed on all positive samples. Amplified DNA fragment of 18S rDNA was sequenced and compared with reference genes, previously deposited in Genbank database.
The number of diarrheic and non-diarrheic patients participated in the study was 134 (44.66%) and 166 (55.34%), respectively. Three subtypes 1, 2, 3 were identified from positive samples. Subtype 2 was the most prevalent (36.5%) followed by subtype 1 (33.3%) and subtype 3 (30.2%). There were no mixed subtypes. Furthermore, the most prevalent subtypes in diarrheic and non-diarrheic patients were subtype 2 (39.28%) and subtype 1 (37.14%), respectively.
Blastocystis sp., is one of the most prevalent unicellular parasites among diarrheic and non-diarrheic patients. Indeed, ST2 was the most prevalent subtype particularly in those samples collected from diarrheic patients.

Giardiasis is the most common pathogenic gastrointestinal parasite worldwide and transmitted by ingesting parasite cyst, through water and food and person-to-person contact. Therefore in food handlers and child care workers it is of high importance. In this study we surveyed the job of individuals with giardiasis.
This study was a pilot descriptive-analytic study. Hundred and nine stool samples were collected from individuals referred to medical centers affiliated to Tehran University of Medical Sciences for health certificate.
Samples were examined with wet mount smear and formol-ether concentration methods. Also a questionnaire was given to each individual.
Sixty nine samples were infected with Giardia lamblia. among positive samples for Giardia lamblia 25 (36.23%) were related to food handlers and occupations which are most frequently associated with food, one (1.44%) nurse, one (1.44%) managing director of the nursery, two (2.89%) housekeepers and one servant (1.44%).
Person-to-person Giardia lamblia transmission is often associated with poor hygiene and sanitation, most commonly by food handlers.
Also, day- care workers have a higher risk of infecting children attending day-care centers. Therefore particular attention should be paid to health of this workers as well as three times stool examination.

As a waterborne pathogen, Cryptosporidium is one of the most common causes of gastroenteritis in human and hoofed livestock animals. This study aimed to investigate the distribution of Cryptosporidium spp. in human and livestock wastewaters in Iran, by the 18S rRNA sequence analysis.
A total of 54 raw wastewater samples collected from three urban treatment plants and two slaughterhouses during 2014-2015 in Tehran, Iran. The presence of the Cryptosporidium oocysts was assessed by immunofluorescence with monoclonal antibodies. To characterize the oocysts at the molecular level, the 18S rRNA gene of Cryptosporidium was PCR amplified and sequenced.
Of the 54 wastewater samples examined, 34 (62.9%) were positive for Cryptosporidium oocysts using the IFA. Of these, 70.5% (24/34) were positive by PCR, that 91.6% (22/24) were successfully sequenced. The species of C. andersoni (95.4%) and C. xiaoi (4.6%) were detected in livestock wastewater samples.
C. andersoni was the major Cryptosporidium sp. found in the aquatic environmental wastewater samples. The high rate of detection of C. andersoni in domestic wastewater was probably the result of the predominancy of this species in cattle herds in Iran. The current study is the first report of C. xiaoi in Iran.

Cryptosporidium and Isospora are known as one of the main cause of diarrhea in both immunocompetent and immunocompromised subjects, all over the world. Incidence of enteropathogens such as Cryptosporidium spp. and Isospora belli considerably has increased, since immunodeficiency virus (HIV) rapidly disseminated. In addition, cancer patients are highly susceptible to opportunistic infections. This study aimed to estimate the prevalence of cryptosporidiosis and isosporiasis in immunocompromised patients in Tehran.
This study carried out on patients admitted to Imam Khomeini hospital during 2013-2014. Stool samples collected from 350 immunocompromised patients. Formol-ether concentration was performed for all stool samples. Zeil-Neelsen technique was applied to stain the prepared smears and finally, all slides were examined by light microscope.
Out of 350 patients, 195 (55.7%) and 155 (44.3%) were male and female, respectively. Cryptosporidium oocysts were detected in 3 (0.9%) samples including one sample from HIVﰂ patients and 2 samples from organ transplant recipients. Isospora oocysts were detected in 4 (1.1%) samples consisting 2 HIVﰂ patients, one patients suffering from malignancy and one patients with other immunodeficiency diseases.
Cryptosporidium sp, and I. belli are the most prevalent gastrointestinal parasitic protozoans that infect a broad range of individuals, particularly those patients who have a suppressed or deficient immunity system.

Intestinal parasitic infections have a worldwide distribution. High prevalence of intestinal parasitic infections in individuals with low socioeconomic status and environmental conditions was found. No study has ever been conducted on the prevalence of these infections in Jiroft. Therefore, in this study prevalence of intestinal parasitic infections was evaluated in Jiroft, Kerman Province, Iran.
A total of 1060 individuals from rural and urban areas of Jiroft were sampled accidentally, during 2013-2014. Fresh stool samples were collected from all individuals and examined by formalin ether concentration and agar plate culture. Direct examination was performed on watery samples.
Out of 1060 individuals, 563 (53.1%) and 497 (46.9%) people were from rural and urban areas, respectively. In general, 297 individuals (28%) were infected with intestinal parasites. The prevalence of infection for protozoa and helminthes infections were 27.4% and 1.8%, respectively. The most prevalent protozoans were Blastocystis hominis (13.7%) and Giardia lamblia (7.8%), and that of helminth was Hymenolepis nana (1.1%).
Intestinal protozoan parasites were more prevalent than helminth parasites. Source of water supply and personal hygiene were important factors in the distribution of parasites in the study area.

Among the most important parasitic disease, causing diarrhea, Gi­ardia lamblia is noteworthy. Nowadays detection methods for these parasites in­clude parasitological methods such as microscopic examination. The sensitivity of these methods relies on the expertise and experience of examiners. In contrast, molecular methods such as PCR are less dependent on the expertise of the exam­iner. Here we developed a PCR for the detection of G. lamblia genome in stool samples in comparison with microscopy, which is the gold standard.
For the evaluation of primers, 22 positive samples and 47 negative samples were used. QIAamp DNA Stool Mini Kit (QIAGEN, Germany) was used for DNA extraction from feces. Primers for PCR were designed using Primer-BLAST which uses Primer 3 to designing specific primers (NCBI/ Primer-BLAST).
Sensitivity of the PCR was done with 100% (95%CI: 84.56-100) for the detection of G. lamblia DNA isolated from patients stool samples which were posi­tive for G. lamblia cysts and/or trophozoites using microscopy as gold standard. In comparison with microscopy, PCR had showed the specificity of 97.87% (95%CI: 88.71-99.95).
We designed new primers for the Giardia, and PCR method for the rapid and accurate identification of Giardia parasites established. With considera­tion to the routine diagnosis techniques in medical parasitology and their limita­tions such as time consuming, laborious, less sensitivity etc. This G. lamblia PCR is a sensitive and specific application for the diagnosis of G. lamblia and provides us a reliable method in the routine intestinal parasitic infection laboratory diagnosis.

Metronidazole, a 5-nitroimidazole derivative, is the main antitrich­omonal agent of choice for treatment of trichomoniasis. Since 1962, some cases of treatment failure with metronidazole have been reported and recently drug re­sistance is now on the rise in the world. This study was aimed to determine current susceptibility of Iranian isolates of Trichomonas vaginalis to metronidazole.
This study was performed on 50 T. vaginalis isolates collected from west and central areas of Iran. After axenisation of the parasites, susceptibility testing was carried out by using serial twofold dilutions of metronidazole (400 to 0.1 µg/ml). The minimum inhibitory concentration (MIC) and the minimum lethal concentration (MLC) of the trichomonads were determined after 48 h incubation at 35.5 °C. Drug susceptibility assays of the all isolates were carried out two times in triplicate under aerobic and anaerobic conditions.
Ninety-eight percent of the T. vaginalis isolates (49/50) were sensitive to metronidazole. Metronidazole resistance was defined as aerobic MIC ≥50 µg/ml, detected in one isolate. The means of aerobic MICs and MLCs and that of anaero­bic MICs of the parasites were 2.91, 1.95 and 0.28 µg/ml, respectively.
This investigation showed in vitro low-level tolerance to metronida­zole in a few T. vaginalis isolates that may be leading to the development of drug resistance.

Free-living amoeba (FLA)-related keratitis is a progressive infection of the cornea with poor prognosis. The present study aimed to investigates the con­tact lenses of patients with keratitis for pathogenic free-living amoebae. Overall, 62 contact lenses and their paraphernalia of patients with kerati­tis cultured and tested for the presence of free-living amoebae using morphological criteria. Unusual plates including plates containing mix amoebae and Vermamoeba were submitted to molecular analysis. Out of 62 plates, 11 revealed the outgrowth of free living amoeba of which 9 were Acanthamoeba, one plates contained mix amoebae including Acan­thamoeba and Vermamoeba and one showed the presence of Vermamoeba. These two latter plates belonged to patients suffered from unilateral keratitis due to the mis­used of soft contact lenses. One of the patients had mix infection of Acanthamoeba (T4) and V. vermiformis meanwhile the other patient was infected with the V. vermiformis. Amoebic keratitis continues to rise in Iran and worldwide. To date, various genera of free-living amoebae such as Vermamoeba could be the causative agent of keratitis. Soft contact lens wearers are the most affected patients in the country, thus awareness of high-risk people for preventing free-living amoebae re­lated keratitis is of utmost importance.

Background and Strongyloidiasis is prevalent in Northern provinces in Iran. Therefore، this study aimed at investigating the prevalence of Strongyloides stercoralis and other intestinal parasites in rehabilitation centers in Mazandaran Province، north of Iran. A cross-sectional study was carried out in seven rehabilitation centers in Mazandaran Province، 2013-2014. Fecal samples were collected from 341 participants (239 male، 102 female) aged 11-86 years old. The centers and specimens were randomly selected. All samples were examined by formol-ether concentration and agar plate culture. Diarrheic samples were examined by direct smear and Trichrome staining. Statistical analysis was performed in SPSS V. 16. Intestinal parasitic infection was observed in 112 individuals. Protozoa infections were seen in 19. 6% and helminth infections were seen in 14. 1%. Strongyloides stercoralis was detected in 2. 1% of the samples. The infection rate with other helminth parasites included Dicrocoelium dendriticum 7. 9%، Trichuris trichiura 3. 2%، Echinostoma sp. 0. 9%، Taenia 0. 3%، and Trichostrongylus sp. 0. 3%. Entamoeba coli was the most common protozoan parasite (19. 4%) followed by Iodamoeba butschlii (2. 1%) and Chilomastix mesnili (1. 2%). This study showed high infection rate with some intestinal parasites. The problems and complications associated with these parasites call for prompt diagnosis and treatment of infected individuals in rehabilitation centers.

Microsporidia species are obligatory intracellular agents that can in­fect all major animal groups including mammals, birds, fishes and insects. Whereas world­wide human infection reports are increasing, the cognition of sources of infec­tion particularly zoonotic transmission could be helpful. We aimed to detect zoono­tic microsporidia spore in fecal samples from some animals with close – contact to human. Overall, 142 fecal samples were collected from animals with closed-con­tact to human, during 2012-2013. Trichrome – blue staining were performed and DNA was then extracted from samples, identified positive, microscopically. Nested PCR was also carried out with primers targeting SSU rRNA gene and PCR products were sequenced. From 142 stool samples, microsporidia spores have been observed microscopi­cally in 15 (10.56%) samples. En. cuniculi was found in the faces of 3 (15%) small white mice and 1 (10%) laboratory rabbits(totally 2.81%). Moreover, E. bieneusi was detected in 3 (10%) samples of sheep, 2 (5.12%) cattle, 1 (10%) rabbit, 3 (11.53%) cats and 2 (11.76%) ownership dogs (totally 7.74%). Phylogenetic analysis showed interesting data. This is the first study in Iran, which identified E. bieneusi and En. Cuniculi in fecal samples of laboratory animals with close – contact to human as well as domesticated animal and analyzed them in phylogenetic tree. E. bieneusi is the most prevalent microsporidia species in animals. Our results can also alert us about potentially zoonotic transmission of microsporidiosis.