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Background and purpose: India and Iran are an important endemic focus of cystic hydatid disease (CHD), where several species of intermediate host are commonly infected with Echinococcus granulosus. Strain characterization of E. granulosus is significant for the development of an effective control programme and to asses the infectivity. In present study, genetic variations in tapeworms causing cystic echinococcosis in the North of India and Iran were investigated and compared.
Materials and methods: Isolates of E. granulosus were collected from buffalo (India) and sheep, cattle, and camel isolates from Iran. PCR linked RFLP approach of ITS1 region of rDNA. Repeat was used in the present study to characterize buffalo isolates from sheep, cattle and camel. 17 pooled samples of protoscoleces from various animals were used for DNA extraction and PCR-RFLP analysis respectively. The PCR products of each isolates were digested separately with 5 restrictive endonucleases enzymes (AluI, HhaI, MspI, TaqI and EcoRI).
Results: Based on the PCR-ITS1 method, the buffalo (liver and lungs) isolates have shown different genotypes and the sheep, cattle and camel isolates appeared to have the same genotype. The RFLP patterns of buffalo lung isolates differed from liver isolates with Taq1 and Hha1, however, showed a similarity with Msp1, EcoR1 and Alu1. Furthermore, differences in numbers and sizes of bands were also observed between buffalo, sheep and camel isolates with Taq1 and Msp1. The sheep and camel isolates differ in the number and sizes of fragments with Msp1 and Taq1. The buffalo lung isolate were quite different from other isolates, with the liver isolate showing a similarity with the sheep isolate. RFLP pattern of isolates from sheep and camel origin was identical, along with the same patterns. Moreover, the existence of buffalo strains (G1 and G3) and sheep strain (G1) were confirmed and our results support the previous studies in Northern India and Iran. These results are relevant for the possibility of transmission of G1 and G3 genotype, between livestock, animals and humans.
Conclusion: It can be speculated that buffalo lung isolates represent G3 genotype and liver isolate as G1 genotype. Further, the existence of sheep (G1) strain was also confirmed in Iran by this study. However, more molecular studies, particularly, mitochondrial gene and amino acid sequencing are required, which can provide valuable data for a better understanding of the differences between different cysts localization.

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Background and purpose: Hepatitis Ç Virus (HÇV), one major factor causing chronic liver disease, has been classified into six major genotypes based on the variation in the genome sequencing. Various genotypes of this virus are associated with the intensity of liver tissue changes in patients with hepatitis Ç. Therefore, this study aims to investigate the relationship between the HÇV genotypes and liver damages.
Materials and methods: This cross-sectional study was conducted on 86 HÇV positive patients referring to Razi Üniversity Hospital in Qaemshahr from 2007 to 2010. Real time polymerase chain reaction (RT-PÇR) test was employed in order to determine the genotypes of HÇV. Moreover, histological activity index of the biopsy (Knodell score) was calculated through staining and the amount of ÂLT and ÂST Sera were measured.
Results: Âmong the samples taken from the patients under study, 3a genotype was seen in 58.2% and 1a/b genotype existed in 41.8% of them. The mean serum levels of ÂST and ÂLT were 89.5 ± 60.8 and 103.7 ± 79.4 ÏÜ/lit, respectively. The histological activity index in 13.1% was at low level, in 41% at moderate level, and in 45.9% at high level. No significant difference was observed in the mean scores of Knodell in different HÇV genotypes (P<0.05), while there was a positive correlation between ÂST and ÂLT level and the mean score of Knodell (P<0.05).
Çonclusion: The findings of this study indicated that there was no significant correlation between HÇV genotype and histological activity index of the patients. However, the serum levels of ÂST and ÂLT increased with the increase in the histological activity index.

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Background and purpose: Giardia and Blastocystis are common parasites of humans with a wide range of hosts. The aim of this study was to identify the genotypes of Giardia intestinalis and Blastocystis hominis in individuals attending Bavi health centers in Khuzestan province, Iran.
Materials and methods: In this study, 30 positive stool samples of Giardia and Blastocystis were collected from individuals attending Bavi health centers in 2019-2020. Then DNA extraction was performed on fecal samples. PCR was performed using GDH gene for Giardia and 18S rRNA region for Blastocystis and PCR products were drawn to determine sequence type and phylogenetic tree.
Results: Sequence analysis was performed on PCR products from Giardia based on amplification of GDH gene. Based on the results of DNA sequence, all identified samples belonged to assemblage BIV. Sequence analysis was performed on PCR products from Blastocystis according to amplification of 18S rRNA gene and all identified samples belonged to ST3 subtype.
Conclusion: The study showed that the predominant genotype of Giardia in Bavi was BIV which indicates a zoonotic cycle in this region. In addition, the predominant subtype of blastocystis was previously reported in this region (ST3) often seen in human-to-human transmission cycle, although there have been reports of animal-to-human cycle. Therefore, alongside health measures to control these two parasites in this area, molecular epidemiology studies in local animals is necessary to determine the zoonotic transmission of Giardia and Blastocystis parasites in this region.