Dataset Information

Clinical, molecular and cytopathological characterization of a Newcastle disease virus from an outbreak in Baghdad, Iraq.

ABSTRACT: BACKGROUND:The frequent outbreaks of Newcastle disease virus (NDV) in Iraq pose a constant threat to commercial poultry, despite the introduction of routine vaccination programmes. Several factors, particularly stress factors and coinfections, might play a role in increasing NDV outbreaks in poultry species. OBJECTIVES:The current study was aimed to characterize an NDV isolate from an outbreak in North Baghdad, Iraq. METHODS:Clinical pathogenicity of the isolate was determined experimentally in chickens. In vitro studies included cytopathological examination, as well as molecular and phylogenetic analyses. RESULTS:Based on the clinical studies and pathogenicity indices (mean death time and intracerebral and intravenous pathogenicity indices), the isolate was characterized as velogenic (highly virulent). Reverse transcriptase polymerase chain reaction targeting the partial fusion protein gene of the NDV genome confirmed the detection. Partial sequencing of the hypervariable region of the fusion gene identified the presence of an avirulent (lentogenic) fusion protein motif (GRQGRL). Phylogenetic analysis of the new isolate along with previously known regional isolates revealed that the new isolate was related to genotype II strains. Additionally, sequence analysis indicated a distinct genetic lineage of the new isolate, which was related to some of the lineages identified in previous outbreaks in the Middle East. CONCLUSION:The current study offers essential information on the epidemiology, characteristics and diagnosis of NDV for disease control in Iraq. The isolate was found to belong to genotype II and possess an avirulent fusion protein motif.

SUBMITTER: Al-Shammari AM

PROVIDER: S-EPMC7397900 | biostudies-literature | 2020 Aug

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Clinical, molecular and cytopathological characterization of a Newcastle disease virus from an outbreak in Baghdad, Iraq.

Al-Shammari Ahmed M AM Hamad Mohammed A MA Al-Mudhafar Murtadha A MA Raad Khansaa K Ahmed Aeser A

Veterinary medicine and science 20200331 3

<h4>Background</h4>The frequent outbreaks of Newcastle disease virus (NDV) in Iraq pose a constant threat to commercial poultry, despite the introduction of routine vaccination programmes. Several factors, particularly stress factors and coinfections, might play a role in increasing NDV outbreaks in poultry species.<h4>Objectives</h4>The current study was aimed to characterize an NDV isolate from an outbreak in North Baghdad, Iraq.<h4>Methods</h4>Clinical pathogenicity of the isolate was determi ...[more]

PMID: 32233074

Similar Datasets

Project description:Newcastle disease (ND) is a devastating worldwide disease of poultry characterized by increased respiration, circulatory disturbances, hemorrhagic enteritis, and nervous signs. Sequence analysis shows several amino acid residue substitutions at neutralizing epitopes on the F and HN proteins of recent Shaanxi strains. Both Cross protection and cross serum neutralization tests revealed that the traditional vaccine strains were unable to provide full protection for the flocks.To better understand the epidemiology of Newcastle disease outbreak, a portion of the F gene and the full-length HN gene were amplified from Shaanxi isolates by reverse transcription-polymerase chain reaction (RT-PCR) and then conducted sequence and phylogenetic analyzes. In pathogenicity analysis, both high intra-cerebral pathogenicity index (ICPI) and mean death time (MDT) tests of chicken embryo were carried out. Furthermore, a cross-protection experiment in which specific-pathogen-free chickens vaccinated with a LaSota vaccine strain were challenged by the recent Shaanxi strain was also performed.Nine Newcastle disease (ND) virus (NDV) isolates which were recovered from ND outbreaks in chicken flocks in China were genotypically and pathotypically characterized. Amino acid sequence analysis revealed that all the recent Shaanxi-isolated NDVs have (112)R-R-Q-K-R-F(117) for the C-terminus of the F2 protein and exhibit high ICPI and MDT of chicken embryos, suggesting that they were all classified as velogenic type of NDVs. Phylogenetic analysis of these isolates showed that they belong to subgenotype VIId that have been implicated in the recent outbreaks in northwestern China. The percentage of amino acid sequence identity of F protein between recent Shaanxi stains and five vaccine strains was in the range of 81.9 %-88.1 %, while the percentage of amino acid sequence identity of HN protein between recent Shaanxi strains and vaccine strains was in the range of 87.4 %-91.2 %. Furthermore, a number of amino acid residue substitutions at neutralizing epitopes on the F and HN proteins of these isolates were observed, which may lead to the change of antibody recognition and neutralization capacity. A cross-protection experiment indicated that specific-pathogen-free chickens vaccinated with a LaSota vaccine strain was not capable of providing full protection for the flocks that were challenged by the recent Shaanxi strain.Taken together, our findings reveal that recent Shannxi NDVstrains exhibit antigenic variations that could be responsible for recent outbreaks of NDVs in northwestern China.

Dataset Information

Clinical, molecular and cytopathological characterization of a Newcastle disease virus from an outbreak in Baghdad, Iraq.

Publications

Clinical, molecular and cytopathological characterization of a Newcastle disease virus from an outbreak in Baghdad, Iraq.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets