Iranian Journal of Virology
Volume:15 Issue: 1, 2021

Enteric diseases have had detrimental impacts on commercial poultry through depressing growth rates and caused considerable economic losses to poultry producers. Chicken astrovirus (CAstV) is one of the most common viruses related to enteric diseases in chickens, especially in young chicks.

Chicken astroviruses were detected by reverse transcriptase and polymerase chain reaction (RT-PCR) in intestinal contents collected from commercial chickens. RT-PCR test amplified a fragment of 601 base pairs located in conserved regions within the ORF 1b (RNA polymerase) gene.

Astroviruses were detected in birds from 36 poorly performing flocks with signs of enteric disease or retarded growth. In total, chicken astroviruses were discovered in pooled intestinal contents of 16 (44.4%) affected broiler flocks, while twenty flocks were negative (55.6%). Phylogenetic analysis based on a 601-bp segment of the ORF1b gene revealed two subgroups of Iranian astroviruses.

Thus, this study discloses the presence of chicken astroviruses in broiler chickens in Iran with enteric problems and stunting syndrome for the first time.

The end of 2019 has marked the year, which the human population encountered a novel virus; SARS-CoV-2 that causes a disease namely COVID-19. Here we focused on the genome and protein mutations and subsequently suggested a new classification of the SARS-CoV-2.

Our study showed that some extra positions in the virus genome play a key role in the SARS-CoV-2 classification. Based on the analysis of the whole genome sequences of 93 viruses.

mutations were classified into nine divisions including IA-1, IA-2, IA-3, IB, II, L1, L2, L3 and S. Totally, 279 mutations were found in the SARS-CoV-2 genomes. 24 mutations lead to the amino acid frame shifting, of which 15 mutations lead to positive frame shifting in amino acids sequences.

Sequence alignment of these positions with that of ancestors showed no change suggesting that they might have occurred in the SARS-CoV-2 genomes to adapt itself to humans.

Apricot latent virus (ApLV) is a species within Foveavirus genus (Betaflexiviridae family, Tymovirales order). Phylogenetic analyses using different ORFs nucleotide sequences divided most ApLV isolates into two clusters. However, there is little data about the sources of genetic differentiation among ApLV isolates.

Partial coat protein (CP) sequences of two Iranian ApLV isolates were determined. The complete or partial CP sequences of ApLV isolates available in the GenBank with two partial CP sequences of Iranian isolates were used for phylogenetic analyses. Also, non-overlapping regions of ORFs were considered for molecular analysis using PATRISTIC, MEGAX, and Phylip 3.67 softwares.

High nucleotide diversity 0.0 to 39.2 % was indicated for TGB2 gene, followed by CP 0.0 to 30.9 %, RdRp 0.0 to 30.3% and TGB1 0.0 to 25.9 % genes. Although Caserta12 and SB12452 isolates showed the low nucleotide diversity in RdRp, TGB1 and TGB2 genes, but high nucleotide diversity was indicated for them in CP gene (26.7 to 30.9 %). Alignment of CP indicated insertion/deletion may affect the phylogenetic differentiation of ApLV isolates. Comparision of nucleotide diversity within and between groups showing that founder effect may affect the variation of ApLV isolates. The values of FST between ApLV phylogenetic groups were < 0.33 indicating a relative rate of dissociation. Recombination breakpoints were detected in the different ORFs especially in Caserta12 isolate from Italy. The ω ratios (dNS/dS) in various proteins were conserved from 0.035 to 0.073. The ENC plot analysis indicated that the codon usage is affected by selection instead of mutation pressure for all genes except TGB2 gene. In addition, the results of mean CAI values indicated the TGB2 gene as a high expression gene. The genetic exchanges by recombination were also correlated with the appearance of new ApLV strains. ENC-Plot and mean CAI analysis are evaluated for the first time in this study to better explains the evolutionary process and fitness of ApLV.

Altogether, our analysis indicated that recombination, mutation and selection pressure are the major sources of genetic differentiation among ApLV isolates.

Avian influenza (AI) is an acute infectious disease of poultry, waterfowl, wild birds, and animals, zoonotically transmitted to humans. Some incidents of HPAI are reported in Iran: H5N1 and H5N8. Iranian Veterinary Organization decides on vaccination (H5) of layer and breeder flocks in high-risk provinces following the outbreak in Iran. This study aimed to evaluate the serum response of the vaccine in the layer flocks of high-risk provinces.

Ten laying farms (Size: 30000-50000) were selected from Qazvin (no: 2) and Isfahan (no: 8) provinces that received the H5 vaccine (Four farms: 1 time; 6 farms: 2 times of vaccine shots). Twenty-five blood samples were taken from each flock. The HI test was carried out in a U-bottomed microtiter plate and 4 HA units of homologous antigen.

The mean titers of antibodies in the poultry farms that received the vaccine once were 1.87, while those that received the immunization twice were 4.90 (significant difference; p<0.05). Also, if we consider protection baseline 4, 4 out of 6 flocks (~67%) could make it above it. Injection of the vaccine twice also improved CV.

In combination with other control measures such as good biosecurity and monitoring programs, vaccination is considered a suitable and powerful tool to support AI eradication or control programs in endemically infected countries if the Iranian Veterinary Organization (IVO) did regular post-vaccination surveillance and evaluated the flocks for silent infections.

Newcastle disease virus (NDV) as the causative agent of a serious respiratory infection threatens the poultry industry worldwide. The risk of an outbreak of NDV could be restricted by mass vaccination. Here we brought up methodology to generate chitosan (CS)-based NDV nanoparticles as an antigen carrier for delivery into intranasal mucosa.

The NDV antigen was produced in the allantoic cavity of 9-11-day embryonated SPF chicken eggs. The virus was tittered and inactivated by ethylene imine. The CS nanoparticles were prepared by ionic gelation method. The physicochemical properties including size, distribution, charge, and morphology of the particles were evaluated. The CS-based NDV nanoparticles were prepared by encapsulation of the inactivated NDV antigen and validated based on the factors affecting optimal encapsulation. The toxicity and safety of the nanoparticles were assayed using inoculation of HLM cells as well as by administration of SPF chickens.

The CS nanoparticles were produced with an average size of 196 nm and good morphology. After encapsulation of NDV antigen, the mean diameter of the nanoparticles was 328  nm with an encapsulation efficiency of ~83% and loading capacity of ~54%. The electron microscopy study indicated that the particles had a spherical shape. The in vitro cytotoxicity and the in vivo safety of the CS-based NDV nanoparticles results indicated the particles were not toxic either in LMH cells or in chickens.

By considering factors that represent optimal nanoparticles, the safe inactivated NDV nanoparticles were successfully developed. This study lays the foundation for the further development of mucosal vaccines and drugs encapsulated in chitosan nanoparticles. By considering factors that represent optimal nanoparticles, the safe inactivated NDV nanoparticles were successfully developed. These results provide a foundation for the further development of mucosal vaccines based on inactivated antigens for use in chicken.

The role of BK and JC polyomaviruses (BKV and JCV) in the causation of respiratory disease and the natural route of transmission has not well been established. The aim of study was to determine the prevalence of BK and JC viruses in 280 respiratory samples and evaluate their contribution to respiratory disease.

PCR was used to screen specimens for BKV and JCV and either single or multiplex RT-PCR, or real time PCR was used to determine co-infection with other viruses. Positive results were confirmed with sequencing.

Of the 280 samples analysed, eight (2.85 %) were positive for BKV. BKV positive samples were from immunocompetent (n=5; 1.78%) and immunocompromised patients (n=3; 1.07%). The positive samples in the immunocompetent group were patients age range 8 days to 29 years. In the immunocompromised group, BKV positive patients age range 30 years to 69 years. Co-infections were found in 3 (37.5%) of the BKV positive samples. No sample was found to be positive for JCV.

Detection of BKV DNA in respiratory specimens supports previous studies suggesting the respiratory tract may be the primary site for acquisition or infection by BK virus at an early age and also reflect the reactivation of latent or persistent infection with the virus. Respiratory tract may not be considered as a site for JC viral persistent infection.

The use of herbal remedies, either in combination with conventional drugs or as an alternative, is accepted worldwide. Silymarin derived from Milk thistle has evidence-based therapeutic potency for wide spectrum of liver diseases. The current work aimed to study the immune-modulating activity of Silymarin in HCV-infected patients by measuring the effect of pure Silymarin solution on the production of IL-17 and IL-10. Nine HCV-1a infected patients and three healthy controls were entered in this study. The mean age of patients and healthy controls were 45.53 (± 10.21) and 39.9 (±10.88), respectively. The PBMCs were isolated, cultured in 96-well plate and incubated with Silymarin solution (5µg/ml) for 24 hours. The cells and cell culture supernatant of three groups including patients treated with Silymarin, non-treated patients, and healthy controls were then subjected to Real Time PCR and ELISA to measure the levels of inflammatory and non-inflammatory cytokines including IL-17 and IL-10, respectively. Statistical analysis was conducted using SPSS software version 20.0. According to Real Time PCR and ELISA results, the level of IL-17 was significantly reduced in patients treated with Silymarin while the expression of IL-10 was remarkably increased in these patients. The results of this study approved the immunomodulatory properties of Silymarin in HCV-infected patients. Hepatoprotective, antiviral, as well as immune-modulatory properties of the Silymarin make it a potential therapeutic option in patients with chronic hepatitis C.

Bovine leukemia virus (BLV) usually infects B lymphocytes and expresses a cluster of ten microRNAs (miRNAs). The microRNAs produced by the virus in infected B lymphocytes usually constitute about 40% of all the miRNAs of the infected B-lymphocytes. The purpose of this study, bioinformatics investigation was done to identify the number of target genes of each of the BLV- miRNAs. Also, the evaluated of the expression level miRNA-B4-3p, B2-5p, and their target genes TET3, MLL2.

Each miRNA-BLV sequence was obtained from the miRBase sequence database and was then assessed by TargetScan and miRWalk software to investigate the target genes of each miRNA of the virus. In the experimental phase of the study, the infected animals were divided into two groups based on the two forms of BLV+ infection; PL form compared with AL form (Group 1) and BLV+ with normal lymph nodes compared with lymphosarcoma form (Group 2). RNA extraction was performed and cDNA synthesized for genes. qPCR was used to evaluate the expression levels of the miRNA and target genes. The expression levels of two miRNA B4-3p, B2-5p, and two genes TET3, MLL2 in two groups were compared.

The Fold Change (FC) values for B4-3p and B2-5p in group 1 were 22 and 67, respectively. In group 2 for B4-3p and B2-5p were 47 and 133, respectively. But there was no change in the expression level of these two gent MLL2 and TET3 in the two groups.

Despite a significant increase in expression level in B4-3p, B2-5p. there was no significant difference in MLL2 and TET3 expression in group 1and 2.

The novel coronavirus, severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) is causative agent for coronavirus disease 2019 (COVID-19) since the 2019 December. Human coronaviruses are classified in Nidovirales order and Coronavirdiae family. This family includes four genera. The SARS-CoV-2 is a member of Betacoronavirus genera and Sarbecovirus linage (linage B). There is a great number of conducted researches for the therapeutic options, epidemiological aspects, clinical and radiological features and molecular or serological diagnosis for the SARS-CoV-2. There is a verity of the commercially available serological and molecular kits for COVID-19 diagnosis. Also, the WHO recommended molecular approaches for the diagnosis. This recommended list contains different primer and probe sets for SARS-CoV-2 diagnosis and different authors assessed the specificity and sensitivity of this primer and probe sets. In this review, we tried to gather comprehensive information about these diagnosis strategies. Also, there are some studies focused on the antibody response to SARS-CoV-2. By considering the growing amount of the available researches in the field of the serological and molecular diagnosis in SARS-CoV-2 detection, current study was aimed to briefly review the most important advancements in this particular subject area.

One of the major concerns in the world is the Coronavirus Disease 2019 (COVID-19), an infectious disease caused by Severe Acute Respiratory Syndrome Coronavirus-2 (SARS-CoV-2). Although the knowledge is limited about the risk factors for the disease, morbidity and mortality may increase in the patients with some underlying conditions such as cardiovascular disease, hypertension, diabetes, cancer, etc. These diseases can weaken the immune system and affect the body's ability to respond to infectious agents. Therefore, these patients are more at the risk for COVID-19 and also the underlying condition may worsen the severity of COVID-19 infection. On the other hand, SARS-CoV-2 via multiple pathophysiological mechanisms can lead to the progression of the underlying diseases and resulting in a poor outcome. The coronavirus binds to angiotensin-converting enzyme 2 (ACE2) which is expressed on the cells of many organs and it can directly affect tissues. Apoptosis of the cells may occur in patients with acute respiratory disease syndrome (ARDS) due to hypoxia in COVID-19. Moreover, SARS-CoV-2 leads to an imbalanced the immune inflammatory response in some patients which may cause indirectly organ injury. In this review we described the prevalence of COVID-19 in various underlying diseases and the impact of the SARS-CoV-2 in the outcome of these diseases. However, further studies are needed to investigate the prevalence of this new virus in patients with underlying diseases and its effects on the progression of illness.

Hepatitis B is a viral infection that attacks the liver and can cause both acute and chronic disease. Thus, the present study focused on antibody titer among HBV-vaccinated medical students in order to evaluate the efficacy of Hepatitis B vaccine and the associated factors. In this cross-sectional study, 184 medical students were enrolled. Blood samples were taken from the participants in order to detection of antibody against Hepatitis BsAg by ELISA. Data analysis was done by Chi-square and Fisher’s exact tests. According to the obtained results, 1.1% of the students had a negative titer, while another 53.8 % were in the borderline situation; whereas 45.1% produced a positive titer. Furthermore, the results revealed that there was no statistically significant difference between Hepatitis B antibody titer values and variables such as gender (P<0/05). By considering the fact that medical students are at greater risk of HBV infection, it is necessary to schedule the determination of serum anti-HBs titer to improve the immunization programs and to decrease the risk of infection before internship program. Re-vaccination (booster shot) is also necessary for people with low titers anti- HBs or loss antibody and controls their antibody titers, and also in who are considered as high-risk group in the society.

Bovine viral diarrhea virus (BVDV) is considered as worldwide and economically significant infection. The aim of this study was to estimate prevalence of persistent bovine viral diarrhea infection (PI) in industrial dairies of Tehran and Alborz province, Iran. In this cross-sectional study, 102371 blood samples were collected from cattles of industrial dairies of Tehran and Alborz province during 2018. Indirect enzyme-linked immunosorbent assay (ELISA) and Reverse transcription-polymerase chain reaction (RT-PCR) were performed for determination of viral genotypes, including BVDV1, BVDV2, and HOBi like among PI samples. A total of 102371 samples were collected from 76 industrial dairies in Tehran and Alborz province, that 512 cases were PI. All samples were positive for BVDV1 (100%). Other genotypes were not found among PI samples. Prevalence of persistent bovine viral diarrhea infection in industrial dairies in Tehran and Alborz was not high. However, it will be further decreased by implementing control and eradication programs.