Newcastle Disease Research Articles

ABSTRACT Newcastle disease virus (NDV) poses a major challenge to poultry farming in Vietnam as it continues to threaten both economic and food security. Despite vaccination efforts, outbreaks caused by velogenic NDV strains continue to occur, indicating gaps in our understanding of the pathogenicity of these viruses. In this study, a velogenic NDV strain (genotype VII.2) was isolated from vaccinated chickens during an outbreak in southern Vietnam. Whole genome sequencing and phylogenetic analyses confirmed that this isolate belongs to a genotype associated with virulent NDV strains. The strain had an intracerebral pathogenicity index (ICPI) of 1.81 and a mean-death-time (MDT) of 56 h. Experimental infection of domestic chickens showed a rapid onset of severe clinical signs, extensive tissue damage, and a high mortality rate, even in co-housed, uninfected chickens. Virus excretion via the oral cavity and cloaca of the experimental chickens facilitated rapid transmission within the flock. These results underscore the urgent need for enhanced epidemiological surveillance and tailored vaccination strategies to mitigate the impact of NDV outbreaks in Vietnam. This study provides important insights into the pathogenicity, transmission, and lesion profile of NDV genotype VII.2, contributing to the development of effective control measures. RESEARCH HIGHLIGHTS Velogenic NDV genotype VII.2 detected in vaccinated chickens in southern Vietnam. Isolate was highly virulent with ICPI 1.81 and MDT of 56 h. Rapid onset of disease, severe lesions, and efficient oral/cloacal viral shedding. Findings call for improved NDV surveillance and tailored vaccination in Vietnam.

Newcastle disease virus (NDV) is a representative paramyxovirus that usually causes severe infections and substantial economic losses to the global poultry industry. Over the years, NDV has attracted widespread attention as a promising oncolytic virotherapy agent and vector vaccine against many pathogens and an important prototype for elucidating the replication and pathogenesis of other paramyxoviruses. The F and HN glycoproteins are two kinds of glycosylated transmembrane proteins located on the virion envelope that play multiple roles in the virulence, infection, replication, and pathogenicity of NDV. In view of the ability to induce neutralizing and protective antibodies and the similarity in the structural features of the F and HN glycoproteins of NDV and other paramyxoviruses, investigating their structures and functions is beneficial for understanding the viral lifecycle and pathogenesis and developing more effective broad-spectrum antibodies or antiviral drugs against viral infection. This systematic review aims to summarize the structural features and membrane fusion mechanism of the F and HN glycoproteins and their relationships with viral virulence, pathogenic phenotype and thermostability, coupled with the crucial roles of F/HN-host protein/compound interactions in the infection, replication, and pathogenicity of NDV. Additionally, this review also highlights the importance of technologies such as protein‒protein interactome analysis, single-particle cryo-electron microscopy, genome-wide CRISPR/Cas9 library screening, and computational structural biology for providing novel viewpoints on the lifecycle and pathogenesis of NDV and related paramyxoviruses and valuable reference information for the future development of efficient treatment strategies targeting viral glycoproteins.

Newcastle disease virus (NDV) is a promising oncolytic virus, yet requires further optimization. In this study, we engineered an F-gene-chimeric NDV expressing human Interleukin 2 (hIL-2) to enhance the oncolytic efficacy of the NDV Clone30 strain. This recombinant virus, designated ovNDV-28, was then produced in suspension-cultured HEK293 cells. The therapeutic potential of ovNDV-28 was evaluated across multiple cancer cell lines, as well as in the HuH-7 xenograft and B16-F0 syngeneic models. Both in vitro and in vivo results demonstrated that ovNDV-28 significantly improved tumor growth suppression compared to the wild-type NDV. Flow cytometry revealed notable increases in tumor-infiltrating CD3⁺CD4⁺ T cells, CD3⁺CD8⁺ T cells, and CD3⁻CD49b⁺ cells, along with elevated expression levels of IFN-γ, TNF-α, perforin, and Granzyme B within tumor tissue. Comprehensive toxicological assessments conducted on B16-F0 tumor-bearing mice involved intratumoral administration of ovNDV-28 at doses of 1.12 × 10⁶ or 1.46 × 10⁷ PFU/mouse every other day for 14 days. No ovNDV-28-related biochemical, hematological, or histopathological abnormalities were observed. The virus was detected in tumor tissue, mesenteric lymph nodes, abdominal adipose tissue, brain, and biceps femoris, without evidence of blood circulation or viral shedding. This study systematically demonstrates the efficacy, safety, and pharmacokinetics of ovNDV-28, supporting its potential for clinical translation.

Newcastle disease (ND), caused by Newcastle disease virus (NDV), has posed a continuous threat to Iran’s poultry industry since its first detection in the early 1950s, with subgenotype VII.1.1 currently recognized as the dominant circulating strain. To gain deeper insights into the evolutionary dynamics of NDV in Iran, we performed genome sequencing and phylogenetic analysis on 60 viruses isolated from domestic poultry and wild birds between 2017 and 2024. Maximum likelihood and Bayesian phylogenetic analyses of the fusion (F) and hemagglutinin-neuraminidase (HN) genes revealed that all viruses belong to subgenotype VII.1.1, forming a well-supported monophyletic group, indicative of independent evolution of this subgenotype within Iran after its introduction. The F and HN genes displayed high sequence identities of over 97% and 93%, respectively. All viruses contained a polybasic cleavage site in the F gene (R-R-Q/K-K-R↓F), consistent with virulent NDV strains. The estimated evolutionary rates for the F and HN genes were 1.31 × 10⁻³ and 9.62 × 10⁻4 substitutions/site/year, respectively. The most recent common ancestor of the subgenotype VII.1.1 F gene was dated to 2007 (95% highest posterior density: 2004-2008), likely originating from the Middle East. Bayesian skyride analysis showed an exponential increase in viral diversity between 2020 and 2024. Continuous surveillance of NDV in both poultry and wild birds in Iran is essential to track ongoing viral evolution, monitor potential changes in virulence or transmissibility, and identify emerging threats to both poultry and public health.

Viral infections remain a major health concern in psittacine birds, with avian bornaviruses (ABV) causing proventricular dilatation disease (PDD), a chronic and often fatal condition. Ribavirin, a broad-spectrum antiviral drug widely used in human medicine, has shown in vitro (ABV) and in ovo (Newcastle disease virus) efficacy against some avian viruses, but its safety profile in birds is largely unknown. This study aimed to evaluate the safety of prolonged ribavirin administration in healthy cockatiels (Nymphicus hollandicus) aged approximately 6 months. The experiment consisted of experimental group (10 cockatiels) and negative control group (10 cockatiels). Ribavirin was administered to the experimental cockatiels according to the following protocol: orally (by gavage at dose 30 mg/kg body weight [BW]/day) two consecutive 28-day courses (course 1 & 2) separated and followed by 14-day recovery periods, then 15 mg/kg BW/day orally and 15 mg/kg BW/day intranasally for 28 days (course 3). The cockatiels were regularly weighed, clinically examined, and blood was collected for hematological and biochemical analyses. No clinical signs of adverse reactions were observed, neither during the therapy nor for 12 weeks after the therapy. BW changed significantly during the experiment, however without any link to ribavirin treatment. Only hematocrit decreased significantly after the ribavirin course 1. Our results indicate that ribavirin at 30 mg/kg BW, administered orally or in combination with intranasal dosing does not appear to cause apparent clinical or laboratory adverse reactions in cockatiels, except for potential alteration of hematocrit which is, however, too mild to be clinically meaningful. This provides an essential first step toward evaluating ribavirin as a therapeutic option for avian viral diseases.Supplementary InformationThe online version contains supplementary material available at 10.1038/s41598-025-22268-9.

Enhanced protection through genotype-matched bivalent H9N2-Newcastle disease virus vaccination: Comparative efficacy against contemporary field strains in specific-pathogen-free chickens.

Prospect of Newcastle disease virus in clinical neurological tumour diseases.

Genotype-matched recombiant inactivated Newcastle disease virus vaccine confer protection against genotype Ⅻ challenge in geese with maternal antibodies.

Development of a Novel Loop-Mediated Isothermal Amplification (LAMP) for Rapid Diagnosis of Newcastle Disease in Field and Resource-Limited Areas

Mitochondria and their electron transport chain (ETC) constitute the central machinery for cellular energy metabolism and biosynthetic regulation. Disruption of the ETC leads to reactive oxygen species (ROS) production and metabolic imbalance, but its precise role in viral replication and infection remains to be elucidated. In this study, we used Newcastle disease virus (NDV), an important avian pathogen and a promising oncolytic virus, as a model to explore its relationship with cellular mitochondrial metabolism. We demonstrate that NDV infection induces varying degrees of mitochondrial fragmentation, membrane potential dissipation, and ROS production, especially in p53-null H1299 cells compared to p53-wild-type A549 cells. ETC impairment restricts NDV replication primarily by limiting aspartate and pyrimidine nucleotide biosynthesis, rather than through ROS-mediated cytotoxicity or energy depletion. Notably, NDV replication in p53-null cells is highly sensitive to ETC complexes I and III inhibition, which can be rescued by exogenous aspartate or uridine supplementation. Mechanistically, p53 serves as a metabolic buffer, protecting mitochondrial function and maintaining precursor availability during viral infection. These findings elucidate the selective and differential utilization of mitochondrial ETC components by NDV and reveal that p53 status shapes cellular susceptibility to NDV-induced metabolic stress. Our work highlights mitochondrial metabolism and p53 as potential targets for antiviral and oncolytic strategies against NDV.IMPORTANCEThis study uncovers the intricate relationship between Newcastle disease virus (NDV) infection and host cell mitochondrial metabolism, with a particular emphasis on the pivotal regulatory role of p53. As both an important avian pathogen and a promising oncolytic virus, NDV disrupts mitochondrial function and the electron transport chain, leading to p53-mediated alterations in cellular energy metabolism and redox homeostasis. Our findings not only deepen the understanding of NDV-mitochondria interactions but also highlight the central role of p53 in viral infection and oncolytic mechanisms. These insights provide a theoretical foundation and novel therapeutic targets for antiviral and anticancer strategies based on p53 or mitochondrial pathways.

Newcastle disease (ND) is a serious poultry disease in Ethiopia. F gene sequences have shown that the velogenic Newcastle disease virus (NDV) sub-genotype VII.1.1 is prevalent in Ethiopia and other East African countries. However, the F gene sequence alone is not enough to fully understand the pathogenicity, antigenicity, and epidemiological characteristics of NDVs. Whole-genome characterizations of currently circulating virus strains are needed to understand the molecular basis of the pathogenicity and antigenicity differences between vaccine and field strains. In this study, we obtained the complete genome sequences of seven NDV sub-genotype VII.1.1 isolated from chicken farms in Ethiopia and compared them with closely related NDVs and vaccine strains. Whole-genome sequencing revealed that all isolates have genome length of 15,192 nucleotides and are composed of six genes in the order 3'-NP-P-M-F-HN-L-5'. Phylogenetic analysis of the whole genomes showed that sub-genotype VII.1.1 can be classified into three distinct lineages and that the Ethiopian isolates in this study clustered within lineage 1. Unique amino acid substitutions were identified in all six genes of the Ethiopian isolates when compared to closely related NDV strains and commonly used vaccine strains. Some of these substitutions have been linked to antigenic variation. Although sub-genotype VII.1.1 is widespread in Ethiopia and other horn of African countries, to the best of our knowledge, this is the first report describing its whole-genome characteristics in this region. The findings in this study are expected to support effective ND control strategies in the region.

ABSTRACT Newcastle disease, a highly contagious avian illness caused by the Newcastle disease virus (NDV), inflicts substantial economic losses upon the global poultry industry. While NDV is known to enter host cells via multiple pathways, critical aspects of its infection and pathogenic mechanisms, particularly the role of host lipids, remain incompletely understood. Here, we demonstrate that NDV infection strategically manipulates host phosphatidylserine (PS) metabolism to enhance its replication cycle. We found that the NDV hemagglutinin-neuraminidase (HN) protein triggers an elevation in intracellular Ca2+ levels, which in turn activates the host phospholipid scramblase TMEM16F. This activation leads to the externalization of PS to the outer leaflet of the plasma membrane. Consequently, NDV virions budding from these PS-rich membrane domains acquire a PS-enriched envelope. Mass spectrometry analysis confirmed high PS abundance on the viral surface. These PS-decorated progeny virions then engage host cell PS receptors, specifically the receptor tyrosine kinase TYRO3 and T-cell immunoglobulin and mucin domain-containing receptor 4 (TIM-4), to facilitate enhanced viral adsorption and entry. This process, known as “apoptotic mimicry,” represents a novel, parallel entry pathway for NDV. These findings provide new mechanistic insights into NDV-host interactions and identify the PS scrambling and recognition axis as a potential therapeutic target for developing novel anti-NDV strategies.

Newcastle disease (ND) is a major viral infection of poultry caused by virulent strains of avian paramyxovirus type 1, resulting in considerable global economic losses. In Ethiopia, ND outbreaks persist despite vaccination efforts, and the genetic diversity of circulating Newcastle disease virus (NDV) strains remains poorly characterized. Most previous studies have relied on partial genomic data, leaving a gap in whole-genome analysis. This study aimed to provide a comprehensive genomic investigation of NDV in Ethiopia. A cross-sectional study was conducted on 14 commercial chicken farms across five districts in central Ethiopia and parts of the Amhara region. A total of 63 pooled specimens were screened using real-time qRT-PCR. Virus isolation was performed in specific-pathogen-free embryonated chicken eggs and confirmed by qRT-PCR. For molecular characterization, the sequence-independent, single-primer amplification (SISPA) technique was applied to obtain whole-genome sequences from five NDV isolates via Oxford Nanopore sequencing Technology. Of the 63 pooled specimens, 11 (13.8%) tested positive for NDV. Whole-genome sequencing revealed two genome sizes (15,192 and 15,186 nucleotides) and confirmed virulent NDV strains with the characteristic F-gene cleavage site motif (112RRQKRF117), distinct from local vaccine strains (112GRQGR↓L117). Phylogenetic analysis showed that all isolates clustered within genotype VII, with four strains (GenBank: PV189285 - PV189288 ) exhibiting 97.24% similarity to Iranian NDV strains (accession number: ON184061 ) of sub-genotype VII.1.1. This study provides the first whole-genome insight into NDV strains circulating in Ethiopia's poultry industry. The detection of virulent NDV in vaccinated flocks highlights the need for vaccines that are genetically and antigenically matched to circulating strains. Broader genomic surveillance across production systems is essential to guide effective ND control strategies and reduce economic losses.

Newcastle disease (ND) is a devastating viral disease affecting poultry and has a substantial economic impact associated with high morbidity and mortality rates. Effective control measures rely on biosecurity measures and vaccination. However, use of phylogenetically divergent, thermolabile vaccines remains a major constraint for controlling ND outbreaks despite vaccination. To address the gap, the present study was undertaken to assess the thermostability profile of mesogenic (Genotype XIII) Newcastle disease virus (NDV) isolates with the aim of identifying heat-stable strains circulating in Assam, India. Five NDV isolates were assessed for thermostability by subjecting them to a range of temperatures at different time intervals. Among the isolates, AS/KM/18/32 exhibited the highest thermal stability, retaining HA (log2) titer and infectivity (log EID50) at 56°C for 30min, with a half-life of 19.99min and an inactivation rate constant of -0.0348min-1. In conclusion, mesogenic NDV (Genotype XIII) isolates circulating in Assam exhibit variable thermostability, warranting further studies on their biological pathogenicity and immunogenicity with a view to developing genotype-matched thermostable vaccine candidates.

ABSTRACT Goose circovirus (GoCV), recognized as the most economically significant immunosuppressive pathogen in global waterfowl production, causes considerable economic losses annually, and multiprovincial surveillance studies have documented high seroprevalence rates. The critical barrier to combating GoCV has persisted in the complete absence of viable in vitro culture systems, fundamentally limiting pathogenesis studies and vaccine development. In a breakthrough advancement, this study pioneers the first successful establishment of a stable primary goose embryo kidney (GEK) cell culture system for GoCV propagation, achieving sustained viral replication through innovative culture protocol optimization. Comprehensive virological characterization via synchronized growth curve analysis, transmission electron microscopy, and IFA quantification not only confirms efficient viral proliferation but also resolves longstanding debates regarding the intracellular replication mechanisms of GoCV, termed GoCV/369/2020. Pathogenesis trials involving gosling with the novel isolated GoCV revealed unprecedented clinicopathological correlations, revealing severe growth retardation, feather disorders, persistent fecal shedding, and biphasic organ damage progression from acute hypertrophy to chronic atrophy. Most critically, we provide the first experimental evidence linking GoCV infection to catastrophic vaccine failure, showing reductions in the antibody titers of avian influenza virus and Newcastle disease virus. This breakthrough has led to the establishment of poultry industry solutions, such as standardized viral isolation for diagnostics, optimized vaccination schedules, and targeted biosecurity against fecal-oral transmission. This study established a stable in vitro culture system and a pathogenic gosling model for GoCV, elucidating its replication, pathogenesis, and vaccine interference, providing crucial insights for future research and control strategies.

Avian infectious bronchitis virus (IBV) is a globally prevalent and highly contagious avian pathogen that imposes significant disease burden and economic losses on the poultry industry. Given the challenges associated with current vaccine-based immunization strategies, there is an urgent need to develop novel therapeutic approaches for the prevention and treatment of IBV infection. In this study, a newly synthesized compound, N-phenethylphenazine-1-carboxamide (SQXA-12), was evaluated for its potent inhibitory effects on IBV replication. The cytotoxicity assay revealed CC50 values of 151.2 µM in H1299 cells, 147.0 µM in Vero cells, 96.83 µM in DF-1 cells, 166.6 µM in HeLa cells, and 136.7 µM in Mac-145 cells, while the EC50 value of SQXA-12 was determined to be 12.25 µM. Sensitivity tests against a panel of viruses, including vesicular stomatitis virus (VSV), human coronavirus OC43 (HCoV-OC43), porcine epidemic diarrhea virus (PEDV), Newcastle disease virus (NDV), porcine reproductive and respiratory syndrome virus (PRRSV), and avian influenza virus H9N2 (AIV-H9N2), demonstrated that SQXA-12 exhibits potential broad-spectrum antiviral activity against both positive- and negative-sense RNA viruses. Collectively, these findings underscore the promising therapeutic potential of SQXA-12 for the treatment of IBV infection.

Anoikis is a specialized form of programmed cell death triggered by the detachment of cells from the extracellular matrix (ECM). Tumor cells that develop resistance to anoikis acquire the ability to detach, migrate, and colonize distant sites, ultimately leading to the formation of metastatic tumors. Bit1 (Bcl-2 inhibitor of transcription 1), a key effector of anoikis, is released into the cytoplasm upon loss of cell attachment and activates a caspase-independent pathway of apoptosis. Newcastle disease virus (NDV), a pathogen that poses a significant threat to the poultry industry, has also emerged as a promising oncolytic virus capable of selectively targeting and killing tumor cells. However, whether NDV can induce the death of anoikis-resistant tumor cells by activating Bit1 remains unclear. In this study, we utilized physical methods to induce cell suspension as a positive control for anoikis and further examined the expression and cellular localization of Bit1 following NDV infection in tumor cells. The results indicated that both viral infection and cell suspension resulted in partial cell death, accompanied by the translocation of Bit1 from the mitochondria to the cytoplasm and a reduction in its protein levels. Notably, Bit1 expression was found not to significantly affect viral replication. These findings suggest that NDV infection promotes tumor cell death by activating Bit1 translocation, mirroring the effects observed during cell suspension-induced anoikis. In addition, in vivo experiments demonstrated that NDV effectively inhibits the metastasis and growth of melanoma in mice, and that overexpression of Bit1 in tumor cells accelerates this process. This study provides novel insights into NDV-induced tumor cell death and identifies potential targets for understanding the mechanisms of oncolytic virus action.

Avian influenza viruses (AIV) cause severe economic losses in poultry production and pose zoonotic threats, necessitating rapid, field-deployable diagnostics. While real-time PCR is the gold standard, its use is limited in resource-constrained settings. This study aimed to develop and validate optimized loop-mediated isothermal amplification (LAMP) protocols for AIV detection directly at sample collection sites. We optimized Real-Time RT-LAMP and colorimetric LAMP assays targeting the conserved M gene, using primers described in the literature. Analytical sensitivity was assessed with a plasmid standard (106-100 copies/μL); specificity was evaluated against 27 AIV strains (H1-H12) and heterologous avian viruses (Newcastle disease, infectious bronchitis, Gumboro, and laryngotracheitis viruses). Reverse transcription was integrated into the LAMP reaction. Real-Time LAMP with SYBR Green achieved 100% analytical sensitivity (95% CI: 80-100; detection limit: Ct = 38), while colorimetric LAMP (cresol red, malachite green, calcein) detected 102 plasmid copies (Ct = 32) with 91.67% sensitivity (95% CI: 76.1-100). No cross-reactivity occurred. These optimized LAMP protocols offer sensitivity and specificity comparable to PCR, require minimal equipment, and enable rapid AIV screening, significantly enhancing early detection and epidemiological surveillance in field conditions.

Triple-TLR agonists' adjuvanted inactivated Newcastle disease virus vaccine promotes effective Th1/Th2 immune responses and affords protective efficacy in chickens.

Retraction Note: The Immunogenicity of a Novel Chimeric Hemagglutinin-Neuraminidase-Fusion Antigen from Newcastle Disease Virus by Oral Delivery of Transgenic Canola Seeds to Chickens.