Newcastle disease (ND) is regarded as a highly contagious and economically important disease in poultry and has a worldwide distribution. Viral determinants for Newcastle disease virus (NDV) virulence are not completely understood and viruses of different pathotypes can be found at live-bird markets in different geographical areas. The prevalence of Newcastle disease in village poultry in Mozambique is not well documented and strains of NDV involved in yearly outbreaks are unknown. The fusion (F) protein is an important determinant of pathogenicity of the virus and is used commonly for phylogenetic analysis. Newcastle disease viruses from various geographical regions of Mozambique were sequenced and compared genetically to published sequences obtained from GenBank. Samples were collected in three different areas of Mozambique and NDV was isolated by infection of embryonated chicken eggs. Sequence analysis of the F-protein encoding gene was used to classify 28 isolates from Mozambique into genotypes and compare these genotypes phylogenetically with existing genotypes found in GenBank. The isolates obtained from Mozambique grouped mainly into two clades. In the first clade, 12 isolates grouped together with sequences of isolates representing genotypes from Mozambique that were previously described. In the second clade, 16 isolates group together with sequences obtained from GenBank originating from Australia, China, South Africa and the USA. Eleven of these isolates showed a high similarity with sequences from South Africa. The number of samples sequenced (<em>n</em> = 28), as well as the relatively small geographical collection area used in this study, are too small to be a representation of the circulating viruses in Mozambique in 2005. Viruses characterised in this study belonged to lineage 5b, a similar finding of a previous study 10 years ago. From this data, it merely can be concluded that no new introduction of the virus occurred from 1995 to 2005 in Mozambique.

Free-range rural chickens (FRCs) dominate the poultry industry in developing countries and chickens are exposed to multi-host infections, including Newcastle disease virus (NDV). The knowledge about the characteristics of NDV from FRCs is limited. This study investigated the persistence, spread and risks of NDV from FRCs. NDV isolates (n = 21) from unvaccinated FRCs in Tanzania were characterised by conventional intracerebral pathogenicity index (ICPI) and sequence analysis of a partial region of the deduced fusion protein encompassing the cleavage site. Results showed that five isolates were screened as lentogenic, nine as mesogenic and six as velogenic. Phylogenetic analysis of the 21 isolates compared to reference sequences revealed three, four, nine and five isolates in genotypes 1, 2, 3c and 4a, respectively. Genotype 3c also included published sequences of Tanzanian isolates obtained from exotic birds and chicken isolates from Uganda. The analysis showed that NDV were persistently present among chicken populations and possibly spread through live chicken markets or migration of wild birds. Differences in amino acid sequences detected around the cleavage site separated the isolates in six types. However, cleavage site pattern could not fully differentiate mesogenic isolates from velogenic isolates.

Objective: Indonesia is one of the Newcastle disease (ND) endemic countries in the world. An outbreak of the ND virus(NDV) was first reported in Indonesia in 1926. This study aimed to detect, isolate, and classify the NDV by molecular approaches from poultry farms in South Sulawesi Province of Indonesia in 2019. Materials and Methods: As many as 36 pooling samples from the cloacal swab, trachea swab, proventriculus, and spleen tissues obtained from ND-suspected chickens were isolated in 11-day old embryonated chicken eggs type-specific antibody-negative. The viruses were confirmed by reverse transcription-polymerase chain reaction (RT-PCR), followed by sequencing. Results: The results showed that 18 out of 36 pooling samples were NDV-positive based on the isolation result and RT-PCR test. The sequencing results showed that 10 NDV isolates had a motif 112R-R-Q-K-R-F117 in the fusion protein cleavage site region, which suggested that the NDV isolates were of virulent pathotype. The phylogenetic studies based on the F genes partial nucleotide sequence classified the study isolates into NDV virus genotype/subgenotype VII.2. Conclusion: These findings are expected to help provide the latest characteristic information of NDV in South Sulawesi Province to determine the seed vaccine for control strategies of ND. [J Adv Vet Anim Res 2021; 8(1.000): 129-137]

Recurrent infection with Newcastle disease virus in flocks that have received vaccinations and high economic losses in Egypt in the last few years urged us to study the diversity and genetic changes in isolated NDV from chickens and its pathogenesis in other species such as turkey poults. Fifteen positive NDVs were isolated from chicken flocks suffering from a respiratory infection. Sequencing of three isolates out from the 15 NDV positive isolates (20%) revealed that NDV was genotype VII.1.1. When compared to other previously isolated worldwide and Egyptian strains, the three isolates’ amino acid sequences show (99.1-99.8 %) identity with genotype VII.1.1.Thirty four weeks old Black Burzi turkey poults, separated into two groups: control (n=15) and infected (n=15), were used to study the pathogenesis of the isolated NDV genotype VII.1.1. Each afflicted bird was given an inoculation with 0.1 mL of 106EID50 of NDV genotype VII.1.1( ND /chicken /Egypt /Dakahlia /31 /2020) at 4 weeks of age via an ocular route. Proventriculus, conjunctiva, lung, spleen, trachea, and caecal tonsil samples were collected from both groups at (6, 12, 24, 48 hours, and 5 days after infection) and tested for the presence of NDV using Quantitative Reverse transcription-polymerase Chain Reaction (QRT-PCR). The virus was found in the challenged birds’ spleen as soon as 12 hours after infection, followed by the lungs and trachea. After 2 and 5 days after NDV infection, histologically significant lesions were found, particularly in lymphoid organs. It is concluded that the presence of NDV in Egyptian flocks of chickens could induce major disease in commercial turkeys, necessitating the development of novel vaccinations based on the circulating NDV genotype VII.1.1 in Egypt to protect domestic poultry from recurrent infection.

Newcastle disease (ND) is endemic in Angola. Several outbreaks of ND occurred in small backyard flocks and village chickens with high mortality in the southern provinces of the country, Cunene, Namibe and Huíla, in 2016 and 2018. In those years, 15 virulent ND virus (NDV) strains were isolated and grouped within subgenotype 2 of genotype VII (subgenotype VII.2). We now present a study on the thermostability of the isolates, aiming at the selection of the most thermostable strains that, after being genetically modified to reduce their virulence, can be adapted to the production of vaccines less dependent on cold chain and more adequate to protect native chickens against ND. Heat-inactivation kinetics of haemagglutinin (Ha) activity and infectivity (I) of the isolates were determined by incubating aliquots of virus at 56 °C for different time intervals. The two isolates from Namibe province showed a decrease in infectivity of 2 log10 in ≤ 10 min, therefore belonging to the I-phenotype, but while the NB1 isolate from 2016 maintained the Ha activity up to 30 min and was classified as thermostable virus (I−Ha+), the Ha activity of the 2018 NB2 isolate decreased by 2 log2 in 30 min, being classified as a thermolabile virus (I−Ha−). Of the 13 NDV isolates from Huíla province, 10 isolates were classified as thermostable, eight with phenotype I+Ha+ and 2 with phenotype I−Ha+. The other three isolates from this province were classified as thermolabile viruses (I−Ha−). Contribution: This study will contribute to the control and/or eradication of Newcastle disease virus in Angola. The thermostable viral strains isolated from chickens in the country can be genetically manipulated by reverse genetic technology in order to reduce their virulence and use them as a vaccine in the remote areas of Angola.

Repairing wild-type p53 or destroying of mutant p53 is one of the therapeutic targets in cancer. Newcastle disease virus (NDV) is a natural oncolytic virus that has potential as a virotherapy agent in cancer. This virus has been shown to induce cancer cell death. The aim of this study was to determine the expression of p53 in cytoplasm and nucleus of cancer cells and its correlation to the grade of cancer malignancy after NDV therapy in rat fibrosarcoma model. Rat fibrosarcoma model were divided into two groups, i.e., the control group (P0) and the treatment group (P1), each consist of 3 rats. The control group (P0) was injected with 0.5 mL phosphate buffered saline and treatment group (P1) was injected with 0.5 mL NDV Tabanan-1/ARP/2017 intratumorally once a day for four consecutive days. At the end of the study, 15 days post-treatment, all rats were euthanized and fibrosarcoma tissue was collected. Fibrosarcoma tissue was examined using immunohistochemistry to determine p53 expression and histopathological examination with hematoxylin-eosin staining to determine the grade of malignancy. The results of this study, the mutant p53 were more expressed in the control group (P0) than the treatment group (P1). It showed that NDV was significant (P<0.05) to the decrease of mutant p53 expression and positively correlated (P<0.05) to the cancer malignancy in rat fibrosarcoma model. In conclusion, NDV has potential as a virotherapy agent targeting mutant p53 in rat fibrosarcoma models.

The lack of effective therapeutic modalities for mammary cancer is attributed to side effects and therapy resistance, necessitating the exploration of alternative treatment options. Newcastle Disease Virus (NDV) exhibits oncolytic activity, making it a promising candidate for cancer therapy. This study aims to assess the effectiveness of the virulent NDV Tabanan-1/ARP/2017 on the growth of mammary carcinoma. The study involved 15 white female Sprague-Dawley rats induced with mammary carcinoma. After the tumors had developed, the rats were divided into two treatment groups, i.e., treatment 0 (P0) and treatment 1 (P1), which received 500 μL of phosphate-buffered saline and 128 HAU/500 μL of NDV Tabanan-1/ARP/2017, respectively. The rats were euthanized on day 15 post-virotherapy. Rats were necropsied, the tumor was excised to measure its weight, percentage of tumor inhibition, and subsequently routinely processed for histopathological preparations. The tumor weights in each treatment group were 3.70±0.72 and 2.34±0.64 grams, respectively, with a tumor inhibition percentage of 36.62%. The angiogenesis, hemorrhage, and mitotic activity of P1 were lower than those of P0, while inflammatory cell infiltration and areas of necrosis appeared more prominent in the group treated with the NDV. In conclusion, the NDV Tabanan-1/ARP/2017 shows potential as a virotherapy agent for rat mammary carcinoma models.