Laboratory of Virology, National Institute of Agricultural and Veterinary Research, Lisbon, Portugal.
Laboratory for the Production of Veterinary Vaccines, Veterinary Research Institute, Lubango, Angola.
Infect Genet Evol. 2023 Sep;113:105481. doi: 10.1016/j.meegid.2023.105481. Epub 2023 Jul 11.
Newcastle disease (ND) is a highly contagious viral disease that affects many bird species worldwide. This study presents the results of the molecular characterization and phylogenetic analysis of 15 virulent ND viruses (NDV) isolated from chickens during outbreaks reported in 2016 and 2018, in the provinces of Namibe and Huíla, in southern Angola. A 561-nucleotide fragment of the F gene was amplified by RT-PCR and sequenced for molecular characterization. Results showed that in all isolates the amino acid sequence comprising the cleavage site of fusion protein is characteristic of virulent viruses (RRQKR/F). Blast analysis revealed high similarity (99.2%) between two isolates from Huíla province, HLA4 and HLA6, and strain 5620 (GenBank accession number KY747479) isolated from chickens in the neighboring country Namibia, in 2016. The other isolates investigated are more related (97.0%) with strain 6195 (GenBank accession number KY747480), also isolated in Namibia in 2016. Phylogenetic analysis performed by Maximum Likelihood, Neighbor-joining and Bayesian methods revealed that like the strains isolated in Namibia, the isolates from southern Angola also belong to subgenotype 2 of genotype VII (VII.2). The network analysis revealed that NBA1 isolate from Angola is closer to a common ancestor than the isolates from Namibia, suggesting that transmission of ND viruses occurred from Angola to Namibia.
新城疫（ND）是一种高度传染性的病毒性疾病，影响全球许多鸟类物种。本研究介绍了从 2016 年和 2018 年在安哥拉南部楠普拉省和威拉省报告的暴发中分离的 15 株强毒 ND 病毒（NDV）的分子特征和系统进化分析结果。通过 RT-PCR 扩增了 F 基因的 561 个核苷酸片段，并进行了测序进行分子特征分析。结果表明，在所有分离株中，融合蛋白裂解位点的氨基酸序列特征为强毒病毒（RRQKR/F）。Blast 分析显示，来自威拉省的两个分离株 HLA4 和 HLA6 与 2016 年从邻国纳米比亚分离的鸡中分离的株 5620（GenBank 登录号 KY747479）高度相似（99.2%）。调查的其他分离株与 2016 年也在纳米比亚分离的株 6195（GenBank 登录号 KY747480）更为相关（97.0%）。最大似然、邻接法和贝叶斯法进行的系统进化分析表明，与在纳米比亚分离的株一样，来自安哥拉南部的分离株也属于基因型 VII 的亚基因组 2（VII.2）。网络分析表明，安哥拉的 NBA1 分离株与纳米比亚的分离株相比，更接近共同祖先，这表明 ND 病毒的传播是从安哥拉到纳米比亚的。
