background and aims: hdv is a defective satellite virus and classified in genus deltavirus. its disease is related and limited to hbv-infected patients. acute infection of delta agent occurs in two different patterns simultaneous infection with both hbv & hdv or super infection of chronically hbv infected patients that lead to more sever type of hepatitis. according to genetic diversity of geno...

the pb2 protein of influenza a viruses has been shown as host range determinant. in this study pb2gene of five h9n2 isolates from tehran province during the period of 1998-2001 were partially amplifiedand sequenced to do phylogenetic study. iranian isolates could be classified in eurasian lineage according totheir pb2 gene sequences. the pb2 genes of these isolates are different from those of m...

background and aims: avian metapneumovirus (ampv) is rna virus responsible for upper respiratory disease in poultry which is usually accompanied by secondary bacterial infections. in iran, some molecular and serological studies indicated that ampv infection occurred in commercial poultry industry. materials and methods: in this study ampv was molecularly identified and characterized in an affec...

background and aims: hemagglutinin (ha) protein of avian influenza (ai) plays an essential role in the virus pathogenicity. ai h9n2 subtype causes significant economic loss in broiler and layer in poultry farms in iran. ai viruses have a great involvement in evolutionary changes at nucleotide and amino acid levels and vaccines could induce faster rates of such changes. up-dated understanding of...

conclusions overall, results of present study were consistent with the data reported earlier base on 5’ ntr in iranian isolates and revealed genotype ir2 is major genotype in iranian hgv-positive patient. it means there are higher similarities between iranian and europe-usa in hgv ns3 gene. results nucleotide blast results emphasized that most similar sequences to ir ns3 sequences were those fr...

conclusions the prevalence of b. hominis in the study area was lower than that reported for most developed countries, and unlike in other countries in the middle east, st4 was the most prevalent subtype. results blastocystis hominis was found to have a prevalence of 3.33% in the study population. there was no significant association of blastocystis infection with age (p = 0.3) or gender (p = 0....

background: crimean congo hemorrhagic fever virus (cchfv) is a member of the bunyaviridae family and nairovirus genus. it has a negative-sense, single stranded rna genome approximately 19.2 kb, containing the small, medium, and large segments. cchfvs are relatively divergent in their genome sequence and grouped in seven distinct clades based on s-segment sequence analysis and six clades based o...

more than 185 species, strains and unclassified theileria parasites are categorized in the entrez taxonomy. the accurate diagnosis and proper identification of the causative agents are important for understanding the epidemiology, prevention and appropriate treatment. this study aims to discuss the importance of two genes of theileria annulata 18s ribosomal rna (18s rrna) and theileria annulata...