Morphological and Molecular Discrimination of Fasciola Species Isolated From Domestic Ruminants of Urmia City,Iran

Background:

The trematodes of the genus Fasciola (the liver flukes) are among the well-known instances of food-borne parasites worldwide. Differentiation of Fasciola species is important because of their different transmission and epidemiological characteristics. The current study was undertaken to discriminate Fasciola species in the domestic ruminants of Urmia city, Iran.

Methods:

Adult flukes were isolated from the naturally infected livers of the slaughtered water buffaloes and sheep. The flukes were initially identified based on morphological and morphometric parameters. A 618-bp-long fragment of the 28SrRNA gene of Fasciola was amplified by polymerase chain reaction (PCR). The amplified fragment was digested by DraII or AvaII enzymes for a restriction fragment length polymorphism (RFLP) analysis and sequenced for the phylogenetic tree construction.

Results:

Based on the morphometric examination, the flukes belonged to F. hepatica, F. gigantica and an intermediate Fasciola form. The PCR-RFLP analysis was able to differentiate F. hepatica from F. gigantica. While the phylogenetic reconstruction justified, to some extent, the morphological diagnosis, it failed to segregate F. hepatica from F. gigantica identified in this and the previous studies.

Conclusion:

To resolve fully the problem of taxonomy and evolution in Fasciola species, employing a broad range of molecular and morphological approaches is necessary. This is crucial for epidemiological surveys and successful clinical management of their infection.     

Molecular Identification and Differentiation of Fasciola Isolates Using PCR- RFLP Method Based on Internal Transcribed Spacer (ITS1, 5.8S rDNA,ITS2)

Background

In this study, we used both ITS1 and ITS2 for molecular identification of Fasciola species.

Methods

The region between 18S and 28S of ribosomal DNA was used in PCR-RFLP method for molecular identification of Fasciola species. Ninety trematodes of Fasciola were collected during abattoir inspection from livers of naturally infected sheep and cattle from Khorasan, East Azerbaijan, and Fars provinces in Iran. After DNA extraction, PCR was performed to amplify region ITS1, 5.8S rDNA, ITS2. To select a suitable restriction enzyme, we sequenced and analyzed the PCR products of F. hepatica and F. gigantica samples from sheep and cattle. Tsp509I fast digest restriction enzyme was selected for RFLP method that caused the separation specifically of Fasciola species.

Results

The fragment approximately 1000bp in all of the Fasciola samples was amplified and then digested with the Tsp509I restriction endonuclease. Seventy F. hepatica and 20 F. gigantica were identified of total 90 Fasciola isolates.

Conclusion

The new PCR-RFLP assay using Tsp509I restriction enzyme provides a simple, practical, fast, low cost, and reliable method for identification and differentiation of Fasciola isolates.     

Superoxide Dismutase (SOD) Enzyme Activity Assay in Fasciola spp. Parasites and Liver Tissue Extract

Background

The purpose of this comparative study was to detect superoxide dismutase (SOD) activities in Fasciola hepatica, F. gigantica parasites, infected and healthy liver tissues in order to determine of species effects and liver infection on SODs activity level.

Methods

Fasciola spp. parasites and sheep liver tissues (healthy and infected liver tissues), 10 samples for each, were collected, homogenized and investigated for protein measurement, protein detection and SOD enzyme activity assay. Protein concentration was measured by Bradford method and SODs band protein was detected on SDS-PAGE. SODs activity was determined by iodonitrotetrazolium chloride, INT, and xanthine substrates. Independent samples t-test was conducted for analysis of SODs activities difference.

Results

Protein concentration means were detected for F. hepatica 1.3 mg/ ml, F. gigantica 2.9 mg/ml, healthy liver tissue 5.5 mg/ml and infected liver tissue 1.6 mg/ml (with similar weight sample mass). Specific enzyme activities in the samples were obtained 0.58, 0.57, 0.51, 1.43 U/mg for F. hepatica, F. gigantica, healthy liver and infected liver respectively. Gel electrophoresis of Fasciola spp. and sheep liver tissue extracts revealed a band protein with MW of 60 kDa. The statistical analysis revealed significant difference between SOD activities of Fasciola species and also between SOD activity of liver tissues (P<.05).

Conclusion

Fasciola species and liver infection are effective causes on SOD enzyme activity level.     

Identification and Genetic Variation of Fasciola Species from Tabriz,North- Western Iran

Background

Fascioliasis is considered as the most important helminthic infection of cattle and sheep. Traditional approaches using morphological and biologic characters cannot cause a certainty in the accurate and precise identification and intra-specific differences of Fasciola spp. In this study, we identified Fasciola species using ITS-1 marker and described genetic variation of each species of the parasite in isolates from Tabriz slaughterhouse in West Azerbaijan Province, north- western Iran.

Methods

Overall, 100 samples (50 from sheep and 50 from cattle) morphologically detected as Fasciola worms were studied for identification of Fasciola species by PCR-RFLP method and intra-species variation of the parasite using RAPD-PCR technique.

Results

A region of approximately 460bp in all samples was successfully amplified. There were no identifiable variations among the size of PCR products. Two and three fragments in samples correspond to F. hepatica and F. gigantica was seen, respectively, through PCR-RFLP method. No difference was seen in digestion pattern according to host (sheep or cattle). Different types of each species of the parasite was observed using RAPD-PCR technique.

Conclusion

We could have an estimate of frequency of F. hepatica and F. gigantic and different genotypes of the parasite in isolates from one locality in north- western of Iran. By extension of such studies in future to other animal hosts (buffalo and goat) and including more regions to sampling, the reliability of the results and their application for control programs in zoonotic diseases will be increased.     

Molecular Differentiation of Fasciola Species and Characterization of Genetic Diversity of F. gigantica Using NADH Dehydrogenase I (ND1) Gene in the Endemic Areas of Iran

Background:

Fasciola hepatica and F. gigantica are the causative agents of fasciolosis in domestic animals and humans. Based on the morphometric criteria, differential diagnosis between them is problematic. In addition, intermediate forms of Fasciola have been found in Iran, which makes the differentiation more difficult. The aim of the present study was to provide molecular evidence for the existence of F. gigantica in Iran using sequencing analysis of ND1 and PCR-RFLP analysis of ITS2 regions and to study the intraspecies variations of F. gigantica based on mitochondrial ND1 gene polymorphism.

Methods:

Forty Fasciola spp. samples collected from four distinct provinces (Fars, Khuzestan, Gilan, Khorasan Razavi) in Iran were collected for morphological and molecular characterization. In molecular method, PCR-RFLP analysis of ITS2 using pagI restriction enzyme was used as a screening approach for F. gigantica differentiation. Then mitochondrial DNA sequence variations in the ND1 gene were used for phylogenetic analysis.

Results:

Based on the morphometric criteria and RFLP analysis, 14 parasitic samples were initially identified to be F. gigantica. Phylogenetic results showed that there are at least 10 different genotypes of F. gigantica in Iran, which are different from those existing in the GenBank. Twenty-six points out of 410 base pairs of sequenced ND1 gene in 10 varieties of F. gigantica were diagnosed to be polymorphic. From 26 points of polymorphism, only eight resulted in the post-translational amino acid changes in ND1 gene product structure.

Conclusion:

Data revealed noticeable genetic diversity (up to 4.63%) between different varieties of F. gigantica in Iran.     

Detection of Coproantigens by Sandwich ELISA in Rabbits Experimentally Infected with Fasciola gigantica

Background

The study was targeted to report the appearance of coproantigens in feces and circulating antibodies in the serum of Fasciola gigantica experimentally infected rabbits.

Methods

Copro Hyper Immune Serum (HIS) and Excretory-Secretory Hyper Immune Serum (ES HIS) antigens were used in a sandwich ELISA for the detection of F. gigantica antigens in feces of 12 rabbits experimentally infected with different doses of F. gigantica encysted metacercariae (EMC) (10, 25 and 30 EMC). The relation between time of appearance of coproantigens in feces and anti-Fasciola antibodies in serum was evaluated.

Results

The earliest diagnostic coproantigen was recorded at 21^st, 25^th and 28^th day post-infection (p.i.) in groups of rabbits infected with 30, 25 and 10 F. gigantica EMC respectively. Both HIS and ES HIS were able to detect coproantigens in feces of rabbits infected with 30 EMC at day 21 p.i. The appearance of F. gigantica coproantigens in feces of infected rabbits was concurrent to the appearance of anti-Fasciola antibodies in blood (3^rd week p.i.). However, coproantigen has specific ability for direct assessment of active infection with minimal cross-reaction with other heterologous parasitic infections.

Conclusion

The findings hold promise for a more accurate diagnostic technique in the near future for suspected Fasciola infection.     

PCR-RFLP Analysis of 28 SrDNA for Specification of Fasciola gigantica (Cobbold, 1855) in the Infected Lymnaea auricularia (Linnaeus, 1785) Snails from Northwestern Iran

Background

Fasciolosis in livestock is a crucial concern in the globe, mainly due to its impact on human health. The aim of this study was to determine the rate of infection with Fasciola gigantica (Cobbold, 1855) larvae in the field-collected snails of Lymnaea auricularia (Linnaeus, 1785) from northwestern Iran using a molecular approach.

Methods

A total of 6,759 pond snails were collected from 28 freshwater bodies in West Azarbaijan. PCR was performed to amplify a 618-bp fragment of the nuclear 28 SrRNA gene of Fasciola. The PCR products were digested by AvaII restriction enzyme to create restriction fragment length polymorphism (RFLP) patterns specific for the detection of F. gigantica.

Results

Of the total collected snails 496 (7.34 %) were L. auricularia, among which 4.64% (23 out of 496) were infected with a Fasciola species according to the PCR analysis. Only 2.22% (11 out of 496) of the infected snails were from the mountainous areas. The highest Fasciola infection rate recorded in the snails of a single site was 1.81% (9 out of 496 snails). Based on the RFLP pattern, F. gigantica accounted for 2.42% of the infection rates in the study sites.

Conclusion

Application of PCR-RFLP was proven to be a useful approach for valid and robust detection of the infection with F. gigantica in its intermediate host snails. These findings may therefore be applicable for establishment of the control programs against dissemination of the infection in different regions.     

Carbohydrate Detection and Lectin Isolation from Tegumental Tissue of Fasciola hepatica

Background

Fascioliasis is a chronic hepatic disease and may be resulted from mechanical/molecular parasite adhesion to host liver tissue. The aim of this study was to detect surface carbohydrate and lectin, carbohydrate-binding protein isolation that might be responsible of this molecular binding.

Methods

The present experimental work was conducted in the Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Tehran, Iran. Fasciola hepatica parasites were collected from abattoir (Saman, Tehran, Iran) and surface mannose-carbohydrate was detected by fluorescein isothiocyanate (FITC) conjugated lectin (Lentil). Lectin of tegumental tissue from F. hepatica was isolated by affinity chromatography and detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).

Results

Mannose carbohydrate was observed on the surface of tegumental tissue from parasite under fluorescence microscope. Carbohydrate-binding protein or lectin with MW of 50 kDa also was isolated from homogenized tegument of helminth.

Conclusion

These results are important for understanding of molecular pathogenesis of F. hepatica at the chronic phase of fascioliasis     

High-throughput sequencing of Fasciola spp. shows co-infection and intermediate forms in Balochistan,but only Fasciola gigantica in the Punjab province of Pakistan

Fasciola gigantica and Fasciola hepatica are digenetic trematodes causing fasciolosis in ruminants. The host and geographical distribution of both Fasciola species are influenced by environmental and climatic conditions favouring survival and development of free-living stages and intermediate hosts, and livestock management practices. The aim of the present study was to describe the host distribution of the two Fasciola species in buffalo, cattle, goats, and sheep in the Balochistan and Punjab provinces of Pakistan. 359 flukes were collected from a total of 32 livers from the four livestock species. Deep amplicon sequencing of the internal transcribed spacer region 2 of ribosomal DNA (rDNA ITS-2) and mitochondrial nicotinamide adenine dinucleotide dehydrogenase 1 (mtDNA ND-1) loci confirmed co-infection of F. hepatica and F. gigantica in Balochistan and single species F. gigantica infection in Punjab. In Balochistan, co-infections and hybrids of both Fasciola species were identified in cattle, with more F. hepatica detected than F. gigantica. However, F. hepatica was the only species identified in goats, and F. gigantica was the only species identified in buffalo. In Punjab, all flukes were confirmed as F. gigantica in each of the four livestock species. Overall, the results indicate differences in the host and geographical distribution of F. gigantica and F. hepatica, and provide useful knowledge for the development of control strategies for livestock and humans.     

Strongyloides stercoralis: The Most Prevalent Parasitic Cause of Eosinophilia in Gilan Province,Northern Iran

Background

Eosinophilia occurs in a wide variety of situations such as parasitic infections, allergic disorders, and malignancies. Most cases of eosinophilia of parasitic origin, especially those with a tissue migration life cycles consists of human infections by helminth parasites. The aim of present study was to determine the parasitic causes of eosinophilia in patients in a major endemic area of human fascioliasis in Gilan Province, northern part of Iran.

Methods

One hundred and fifty patients presenting with an elevated eosinophilia attending infectious disease clinics with or without clinical symptoms, were examined. After clinical history evaluation and physical examination, coprological examinations were performed using the formalin-ether and the Kato-Katz techniques for detection of Fasciola sp. and intestinal parasites.

Results

Forty two percent of patients were infected with S. stercoralis, nine (6%) were found to be infected with Fasciola sp. while only a single patient (0.7%) were infected by Ttrichostrongylus sp.

Conclusion

Local clinicians in Gilan may consider eosinophilia as a suggestive indication for diagnosis of human fascioliasis, especially when microscopic stool and/or serological tests are negative. Based on the results, local physicians should consider S. stercoralis as the potential causes of eosinophilia in patients with elevated eosinophilia.     

Prevalence of Linguatula serrata Nymphs in Mesenteric Lymph Nodes of Cattle and Buffaloes Slaughtered in Ahvaz Abattoir,Iran

Background

Linguatula serrata, one of the parasitic zoonoses, inhabits the canine respiratory system (final hosts). The objective of this study was to determine the prevalence rate of L. serrata nymphs in mesenteric lymph nodes (MLNs) of cattle and buffaloes (intermediate hosts) that were processed in the Ahvaz, Iran abattoir.

Methods

During November 2010 to March 2011, 223 animals (119 cattle and 104 buffaloes), in different sex and three age groups (<2, 2–< 3 and 3-> 3 years old) were sampled randomly at Ahvaz abattoir. Up to 35 grams of their mesenteric lymph nodes were examined separately for nymphal stages of L. serrata by digesting the samples with acid- pepsin method, collected the nymphs and counted under stereomicroscope.

Results

Overall 37(16.6%) of 223 animals were infected with L. serrata nymphs in their mesenteric lymph nodes. Prevalence of the infection in cattle and buffaloes were 16.8% and 16.3% respectively. The number of collected nymphs of MLNs was ranged from 1 to 16. No significant differences were seen in the infection rates between males and females (sexes) and age groups in the cattle and buffaloes (P <0.05).

Conclusion

Linguatula serrata has an active life cycle in the studied area and a zoonotic potential for transmission between animal and human. Avoiding use of raw MLNs to dogs can help reduce the infection.     

Triclabendazole Effect on Protease Enzyme Activity in the Excretory- Secretory Products of Fasciola hepatica in Vitro

Background

Fasciola hepatica is one of the most important helminthes parasites and triclabendazole (TCBZ) is routinely used for treatment of infected people and animals. Secreted protease enzymes by the F. hepatica plays a critical role in the invasion, migration, nutrition and the survival of parasite and are key targets for novel drugs and vaccines. The aim of study was to determine the protease activity of excretory- secretory products (ESP) of F. hepatica in the presence of TCBZ anthelmintic.

Methods

F. hepatica helminthes were collected and cultured within RPMI 1640 [TCBZ treated (test) and untreated (control)] for 6 h at 37 °C. ESP of treated and control were collected, centrifuged and supernatants were stored at -20°C. Protein concentrations were measured according to Bradford method. Protease enzymes activities of ESP samples were estimated by using sigma’s non-specific protease activity assay. ESP protein bands were detected by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE).

Results

Mean protein concentrations in control and treated of ESP samples were determined 196.1 ±14.52 and 376.4 ±28.20 μg/ml, respectively. Mean protease enzymes activities in control and treated were 0.37 ±0.1 and 0.089 ±0.03 U/ml, respectively. Significant difference between proteins concentrations and protease enzymes activities of two groups was observed (P<0.05). SDS-PAGE showed different patterns of protein bands between treated and control samples.

Conclusion

The TCBZ reduced secreted protease enzymes activities and possibly effects on invasion, migration, nutrition and particularly survival of the parasite in the host tissues.     

Seroprevalence and Risk Factors of Toxoplasma gondii Infection in Buffaloes,Sheep and Goats in Yunnan Province,Southwestern China

Background:

The seroprevalence of Toxoplasma gondii infection in buffaloes, sheep and goats in Yunnan Province, southwestern China was conducted between May 2012 and December 2013.

Methods:

A total of 973 (427 buffaloes, 154 sheep and 392 goats) serum samples were collected from seven administrative regions of Yunnan Province, and examined for T. gondii antibodies by indirect hemagglutination (IHA) test. Some risk factors related to species, age, gender and geographical origin were determined using a multinomial logistic regression.

Results:

The overall seroprevalence of T. gondii in ruminant species was estimated at 11.9%. The final logistic regression model demonstrated that host species and geographical origin were the main risk factors associated with T. gondii infection (P<0.05).

Conclusion:

Taken together, the results of the present study revealed a high exposure to T. gondii in ruminant species in Yunnan Province, which has an important implication for public health.     

Sequence Analysis of the Second Internal Transcribed Spacer (ITS2) Region of rDNA for Species Identification of Trichostrongylus Nematodes Isolated From Domestic Livestock in Iran

Background

Infectivity of herbivores with Trichostrongylus nematodes is widespread in many countries, having a major economic impact on breeding, survivability, and productivity of domestic livestock. This study was carried out on Trichostrongylus species isolated from domestic livestock in order to develop an easy-to-perform method for species identification.

Methods

Trichostrongylus isolates were collected from sheep, goat, cattle, and buffaloes in Khuzestan Province, southwest Iran. Primary species identification was carried out based on morphological characterization of male worms. PCR amplification of ITS2-rDNA region was performed on genomic DNA and the products were sequenced. Phylogenetic analysis of the nucleotide sequence data was conducted employing Bayesian Inference approach. Consequently, a restriction fragment length polymorphism (RFLP) profile was designed to differentiate Trichostrongylus species.

Results

A consensus sequence of 238 nucleotides was deposited in the GenBank for Iranian isolates of Trichostrongylus species including T. colubriformis, T. capricola, T. probolurus and T. vitrinus. The designated RFLP using restriction enzyme TasI could readily differentiate among species having different ITS2 sequence. The molecular analysis was in concordance with morphological findings.

Conclusion

Phylogenetic analysis indicated a close relationship among the sequences obtained in this study and reference sequence of relevant species. ITS2-RFLP with TasI is recommended for molecular differentiation of common Trichostrongylus species.     

Development of an Indirect ELISA Using Different Fragments of Recombinant Ncgra7 for Detection of Neospora caninum Infection in Cattle and Water Buffalo

Background:

Dense granules are immunodominant proteins for the standardization of immunodiagnostic procedures to detect neosporosis. In the presented study different fragment of a dense-granule protein was evaluated for serodiagnosis of Neospora caninum in cattle and water buffalo.

Methods:

NcGRA7, from N. caninum tachyzoites was amplified. PCR product and pMAL-c2X plasmid were digested with EcoR1 restriction enzyme and expressed in Escherichia coli to evaluate its competence for detection of anti- N. caninum antibodies with ELISA in comparison with commercial IDEXX ELISA. Furthermore, 230 sera of presumably healthy cattle and water buffaloes (108 cattle and 122 water buffaloes) were analyzed by both tests to determine the agreement of these two procedures.

Results:

Sensitivities and specificities of NcGRA7-based ELISA were 94.64% and 90.38% respectively using sera of cattle, but were 98.57% and 86.54% in the case of buffaloes respectively. A good correlation between the results of IDEXX ELISA and ELISA based on recombinant NcGRA7 for detecting N. caninum antibodies was appeared. Analyzing by Mc Nemar′s showed that NcGRA7-based ELISA has acceptable capability to differentiate the positive results in comparison with IDEXX ELISA.

Conclusion:

NcGRA7-based ELISA considering utilized new fragment of genomic DNA is a good tool for serodiagnosis of anti- N. caninum antibodies for screening and epidemiological purposes on cattle herd and water buffaloes as well.     

The Prevalence of Cryptosporidium spp. in Children,Taiz District,Yemen

Background

This is the first work done on cryptosporidiosis among the children in Taiz, Yemen.

Methods

A number of 712 samples were collected from children of different ages (ranging from 1 month to 12 years) from Dec 2006 to Aug 2007. The collected samples were examined by Sheather''s sugar floatation and Modified Ziehl- Neelsen stain as well as ELISA methods. The test results were statistically analyzed by SPSS software.

Results

The overall positive percentage was 43.7%. The higher incidence (36.2%) was occurred in males while the lowest incidence (32.7%) was observed in females (r=0.876; P=0.001). The correlation between infected cases and the type of drinking water was r =0.121. Among the cases examined by ELISA (92 cases), 26.1% were infected. The correlation between seropositivity and gender was r=0.652 (P=0.031).

Conclusion

Cryptosporidium spp. is a significant pathogen among children at Taiz. Fresh water supplies, education, eating habits and domestic animals are considered the main sources for transmission of cryptosporidiosis.     

Aspicularis tetraptera Induced Hematological Parameters in Infected and Vaccinated Mice

Background

The present study deals with the effect of helminthic infection as Nematode parasite like Aspiculuris tetraptera on the haematological parameters of infected and vaccinated mice.

Methods

Totally 15 mice were used. Five mice were used for positive control, 5 mice used for negative control and 5 mice used for experiment. The hematological parameters were studied viz. RBC, Hb, and serum protein values.

Results

The mice carrying heavy infection showed decrease in the Hb, RBC, and serum protein but in the vaccinated mice, all studied parameters were become on normal range. The level of immune response was assessed based on above studied hematological parameters in infected and vaccinated mice with Aspiculuris tetraptera.

Conclusion

The increased value of RBC, Hb and Serum protein in infected and vaccinated mice compared to infected and non vaccinated suggested the involvement of blood parameters in immune response. This study also proves that somatic antigen of A. tetraptera was effective in imparting immunity in mice     

Distribution of Fasciola hepatica and F. gigantica in the endemic area of Guilan,Iran: Relationships between zonal overlap and phenotypic traits

Fascioliasis is a zoonotic disease emerging in numerous parts of the world. In any endemic area, the characterisation of scenarios and patterns of infection must always be considered the starting point before implementing any control measure. Fascioliasis is a parasitic disease of different epidemiological, pathological and control characteristics depending on the endemic area and the causal agent, Fasciola hepatica and Fasciola gigantica. Classically it has been accepted that F. hepatica is present worldwide, while the distribution of the two species overlaps in many areas of Africa and Asia. Fascioliasis caused by F. hepatica, F. gigantica and intermediate forms is present in Guilan province, a complicated epidemiological situation where the highest human infection rates have been described in Iran. Morphometric tools were used to analyse the possible relationship between liver-fluke metric traits and geographical and altitudinal distribution. This is the first study in which a detailed distribution of both Fasciola species is analysed in a human fascioliasis endemic area with a zonal overlap transmission pattern. An accurate analysis was conducted to phenotypically discriminate between fasciolids from naturally infected livestock (cattle, buffaloes, sheep and goats). The distribution of the % F. hepatica-like (F.h.) and F. gigantica-like (F.g.) flukes detected in each liver versus altitude (m) in each group was analysed. The presence of F.g. specimens mainly in locations below sea level (average: 11.23% F.h., 88.77% F.g.), the presence of both species with similar intensity at 1–99 m (average: 56.95% F.h., 43.05% F.g.) and the presence of F.h. specimens mainly from 100 to 999 m (average: 71.69% F.h., 28.31% F.g.) as well as in locations with an altitude above 1000 m (average: 97.48% F.h., 2.52% F.g.) are noteworthy. A significant positive correlation was obtained between altitude and % F.h., and a significant negative correlation was obtained between altitude and % F.g. The results show that F.g. populations in cattle, buffaloes and sheep share larger size values, but smaller specimens are present mainly in lowland populations located below sea level, independently of the host species (cattle, buffalo). F.g. from lowland cattle presented larger worm size variability. Four different fascioliasis transmission areas may be distinguished in Guilan: (a) lowland coastal areas neighbouring the Caspian Sea shore, below sea level, where basically F. gigantica-like specimens are found; (b) a coastal plain with an altitude between 1 and 100 m where both species co-exist; (c) areas with altitude values of 100–999 m where mainly F. hepatica-like specimens are found; (d) highland mountainous areas, where basically F. hepatica-like specimens are found. The study of the influence of the host species on the liver fluke was also carried out by a size-out analysis. This is the first report concerning the decisive influence exercised by the host species on the metric traits of F. gigantica adults.     

Seroprevalence of Human Fasciolosis in a New-Emerging Focus of Fasciolosis in Yasuj District,Southwest of Iran

Background

Fasciolosis is an important health and veterinary problem in Iran. The epidemiological pattern of disease has been changed markedly in recent years and there are regions that have potent capacity to be new focus of the disease. One of these areas is Yasuj district in southwest of Iran where animal fasciolosis has been quite common. The current study was conducted to determine the seroprevalence of human fasciolosis in this area and to reveal the epidemiological factors associated with the spreading of the disease in this region.

Methods

One thousand blood samples were randomly collected from five villages in Yasuj district. ELISA, using Fasciola somatic antigen (SA), was carried out to detect anti Fasciola antibodies in the collected sera.

Results

Anti-Fasciola antibodies were detected in serum of 18(1.86%) individuals by ELISA. Out of 18 seropositive people, 9 (0.9) were female and 9 (0.9%) were male. Most of people (99.8%) had a history of consuming wild freshwater plants mainly Nasturtium microphyllum (local name Bakaloo) and/or Mentha logifolia (local name Pooneh). No significant correlation was found between seropositivity to fasciolosis and sex, age, history of consumption of green leafy aquatic plants whereas correlation between seropositivity and abdominal pain was significant (P< 0.05).

Conclusion

Results of this study showed that the seroprevalence rate of human fasciolosis in Yasuj district is relatively high and this area can be considered as a new emerging focus of the disease in Iran.