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1.
Comp Immunol Microbiol Infect Dis ; 65: 110-115, 2019 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-31300098

RESUMEN

The coronavirus avian Infectious bronchitis virus (IBV) poses economic threats to poultry farms worldwide, affecting the performance of both meat-type and egg-laying birds. To define the evolution of recent IBVs in Iran, a genetic analysis based on hypervariable nucleotide sequences of S1 gene was carried out. Tracheal swab samples were collected from 170 Broiler flocks during 2017. Ten tracheal swabs from each flock pooled. From a total number of 170 flocks tested, 84.71% found to be positive. Phylogenetic tree analysis revealed the presence of D274 as a first time in Iran. IS/1494/06 was showed to be dominant IBV type circulating in broiler farms with a significantly higher prevalence than other four genotypes. Considering fluctuations in QX-type prevalence in recent years, continuous monitoring is necessary to reduce economic consequences in layer and broiler farms. The findings highlight the importance of using modified vaccination strategies that are adapted to the changing disease scenario.


Asunto(s)
Infecciones por Coronavirus/veterinaria , Genotipo , Virus de la Bronquitis Infecciosa/genética , Filogenia , Enfermedades de las Aves de Corral/virología , Animales , Pollos , Infecciones por Coronavirus/epidemiología , Granjas , Virus de la Bronquitis Infecciosa/clasificación , Virus de la Bronquitis Infecciosa/aislamiento & purificación , Irán/epidemiología , Enfermedades de las Aves de Corral/epidemiología , Prevalencia , Tráquea/virología
2.
Artículo en Inglés | MEDLINE | ID: mdl-31174704

RESUMEN

During 2014-2017 Clade 2.3.4.4 H5N8 highly pathogenic avian influenza viruses (HPAIVs) have spread worldwide. In 2016, an epidemic of HPAIV H5N8 in Iran caused mass deaths among wild birds, and several commercial poultry farms and captive bird holdings were affected and continue to experience problems. Several outbreaks were reported in 2017. One of them is related to Hooded crow (Corvus cornix) in a national park in Esfahan province in 2017. Whole genome sequencing and characterization have been done on the detected H5N8 sample. Based on HA sequencing results, it belongs to 2.3.4.4 clade, and the cleavage site is (PLREKRRKR/G). Phylogenetic analysis of the HA gene showed that the Iran 2017 H5N8 virus clustered within subgroup Russia 2016 2.3.4.4 b of group B in H5 clade 2.3.4.4 HPAIV. On the other hand, the NA gene of the virus is placed in group C of Eurasian lineage. Complete genome characterization of this virus revealed probable reassortment of the virus with East-Asian low-pathogenic influenza viruses. Furthermore, the virus possessed some phenotypic markers related to the increased potential for transmission and pathogenicity to mammals at internal segments. This study is the first full genome characterization H5N8 HPAIV in Iran. The data complete the puzzle of molecular epidemiology of H5N8 HPAIV in Iran and the region. Our study provides evidence for fast and continuing reassortment of H5 clade 2.3.4.4 viruses, that might lead to changes in virus structural and functional characteristics such as the route and method of transmission of the virus and virus infective, pathogenic and zoonotic potential.


Asunto(s)
Cuervos/virología , Genoma Viral , Subtipo H5N8 del Virus de la Influenza A/genética , Gripe Aviar/epidemiología , Gripe Aviar/virología , Animales , Brotes de Enfermedades , Glicoproteínas Hemaglutininas del Virus de la Influenza/genética , Subtipo H5N8 del Virus de la Influenza A/aislamiento & purificación , Irán/epidemiología , Mutación , Filogenia , ARN Viral/genética , Virus Reordenados/genética , Virus Reordenados/aislamiento & purificación
3.
Trop Anim Health Prod ; 51(6): 1737-1749, 2019 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-30729386

RESUMEN

Since 1998, Iran's poultry industry has faced several outbreaks of low pathogenic avian influenza H9N2. Tissue samples were collected from a broiler flock with respiratory symptoms in autumn 2017. After that, virus isolation and confirmation of H9N2 using RT-PCR, sequencing, and bioinformatic analysis for all eight genes were performed. The phylogenic analysis revealed HA gene of recent Iranian isolate (A/chicken/Mashhad/UT-Barin/2017) which was clustered in G1 sublineage. In addition, all eight genes of the virus were placed with Pakistani isolates of 2015 in separate group. Based on amino acid motif KSSR in HA cleavage site, the UT-Barin is considered as low pathogenic avian influenza with eight HA and seven NA potential N-glycosylated sites. No evidence was detected regarding adamantane and neuraminidase inhibitors' drug's resistance. Multiple point mutations were observed in all genes that were responsible for increasing virulence of the virus for avian host and also increasing affinity to mammalian host cells.


Asunto(s)
Pollos/virología , Subtipo H9N2 del Virus de la Influenza A/genética , Gripe Aviar/virología , Animales , Brotes de Enfermedades/veterinaria , Genoma Viral , Subtipo H9N2 del Virus de la Influenza A/aislamiento & purificación , Gripe Aviar/epidemiología , Irán/epidemiología , Filogenia
4.
Avian Pathol ; 47(5): 509-519, 2018 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-29954188

RESUMEN

Newcastle disease (ND) is a contagious viral disease affecting numerous avian species, particularly domestic poultry, and causes devastating outbreaks. In spite of its endemicity and importance in Iran, data on the genetic characterization of ND virus (NDV) are scarce. An alarming issue that has just been raised is the occurrence of ND outbreaks with unexpected high mortality and severe clinical signs. The present study was conducted to characterize the emerging NDV genetically. An NDV strain, isolated in 2017 from commercial broilers showing severe nervous and enteric signs, was completely sequenced and found to be 15,192 nucleotides in length. The phylogenetic analysis demonstrated that the virus belonged to subgenotype VIIi, a subgenotype with potential panzootic features which has recently emerged in the Middle East and Asia. The supporting genetic pattern obtained from the complete genome, fusion and haemagglutinin gene analysis showed close relationship of the isolate with Pakistani VIIi NDVs. The analysis of the F protein showed a polybasic amino acid motif and a phenylalanine at position 117 at the cleavage site, which is a characteristic of virulent strains. The isolate showed significant differences from the previously characterized NDV strains from commercial and rural chickens in Iran. This may describe the importance of the illegal trade of pet birds from neighbouring countries leading to the emergence of new genotypes. This study introduces a newly emerging NDV VIIi subgenotype in Iran. This investigation emphasizes the necessity of effective control strategies.


Asunto(s)
Genotipo , Enfermedad de Newcastle/virología , Virus de la Enfermedad de Newcastle/patogenicidad , Animales , ADN Complementario , Brotes de Enfermedades/veterinaria , Irán/epidemiología , Enfermedad de Newcastle/epidemiología , Virus de la Enfermedad de Newcastle/clasificación , Virus de la Enfermedad de Newcastle/genética , Filogenia , ARN Viral , Virulencia
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