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Nipah virus (NiV) causes near-annual outbreaks of fatal encephalitis and respiratory disease in South Asia with a high mortality rate (â¼70%). Since there are no approved therapeutics for NiV disease in humans, the WHO has designated NiV and henipaviral diseases priority pathogens for research and development. We generated a new recombinant green fluorescent reporter NiV of the circulating Bangladesh genotype (rNiV-B-ZsG) and optimized it alongside our previously generated Malaysian genotype reporter counterpart (rNiV-M-ZsG) for antiviral screening in primary-like human respiratory cell types. Validating our platform for rNiV-B-ZsG with a synthetic compound library directed against viral RNA-dependent RNA polymerases, we identified a hit compound and confirmed its sub-micromolar activity against wild-type NiV, green fluorescent reporter, and the newly constructed bioluminescent red fluorescent double reporter (rNiV-B-BREP) NiV. We furthermore demonstrated that rNiV-B-ZsG and rNiV-B-BREP viruses showed pathogenicity comparable to wild-type NiV-B in the Syrian golden hamster model of disease, supporting additional use of these tools for both pathogenesis and advanced pre-clinical studies in vivo.
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Batborne henipaviruses, such as Nipah and Hendra viruses, represent a major threat to global health due to their propensity for spillover, severe pathogenicity, and high mortality rate in human hosts. Coupled with the absence of approved vaccines or therapeutics, work with the prototypical species and uncharacterized, emergent species is restricted to high biocontainment facilities. There is a scarcity of such specialized spaces for research, and often, the scope and capacity of research, which can be conducted at BSL-4, is limited. Therefore, there is a pressing need for innovative life-cycle modeling systems to enable comprehensive research within lower biocontainment settings. This work showcases tetracistronic, transcription, and replication-competent minigenomes for the Nipah, Hendra, and Cedar viruses, which encode viral proteins facilitating budding, fusion, and receptor binding. We validate the functionality of all encoded viral proteins and demonstrate a variety of applications to interrogate the viral life cycle. Notably, we found that the Cedar virus replicase exhibits remarkable promiscuity, efficiently driving replication and transcription of minigenomes from all tested henipaviruses. We also apply this technology to Ghana virus (GhV), an emergent species that has so far not been isolated in culture. We demonstrate that the reported sequence of GhV is incomplete, but that this missing sequence can be substituted with analogous sequences from other henipaviruses. The use of our GhV system establishes the functionality of the GhV replicase and identifies two antivirals that are highly efficacious against the GhV polymerase. IMPORTANCE: Henipaviruses are recognized as significant global health threats due to their high mortality rates and lack of effective vaccines or therapeutics. Due to the requirement for high biocontainment facilities, the scope of research which may be conducted on henipaviruses is limited. To address this challenge, we developed innovative tetracistronic, transcription, and replication-competent minigenomes. We demonstrate that these systems replicate key aspects of the viral life cycle, such as budding, fusion, and receptor binding, and are safe for use in lower biocontainment settings. Importantly, the application of this system to the Ghana virus revealed that its known sequence is incomplete; however, substituting the missing sequences with those from other henipaviruses allowed us to overcome this challenge. We demonstrate that the Ghana virus replicative machinery is functional and can identify two orally efficacious antivirals effective against it. Our research offers a versatile system for life-cycle modeling of highly pathogenic henipaviruses at low biocontainment.
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Genoma Viral , Henipavirus , Replicación Viral , Humanos , Henipavirus/genética , Regiones Promotoras Genéticas , Animales , Proteínas Virales/genética , Proteínas Virales/metabolismo , Infecciones por Henipavirus/virología , ARN Polimerasa Dependiente del ARN/genética , ARN Polimerasa Dependiente del ARN/metabolismo , Virus Nipah/genética , Virus Hendra/genéticaRESUMEN
Cedar henipavirus (CedV), which was isolated from the urine of pteropodid bats in Australia, belongs to the genus Henipavirus in the family of Paramyxoviridae. It is closely related to the Hendra virus (HeV) and Nipah virus (NiV), which have been classified at the highest biosafety level (BSL4) due to their high pathogenicity for humans. Meanwhile, CedV is apathogenic for humans and animals. As such, it is often used as a model virus for the highly pathogenic henipaviruses HeV and NiV. In this study, we challenged eight Rousettus aegyptiacus fruit bats of different age groups with CedV in order to assess their age-dependent susceptibility to a CedV infection. Upon intranasal inoculation, none of the animals developed clinical signs, and only trace amounts of viral RNA were detectable at 2 days post-inoculation in the upper respiratory tract and the kidney as well as in oral and anal swab samples. Continuous monitoring of the body temperature and locomotion activity of four animals, however, indicated minor alterations in the challenged animals, which would have remained unnoticed otherwise.
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Quirópteros , Infecciones por Henipavirus , Henipavirus , Replicación Viral , Animales , Quirópteros/virología , Infecciones por Henipavirus/virología , Infecciones por Henipavirus/veterinaria , Henipavirus/fisiología , ARN Viral/genéticaRESUMEN
Nipah virus (NiV) is a highly pathogenic paramyxovirus capable of causing severe respiratory and neurologic disease in humans. Currently, there are no licensed vaccines or therapeutics against NiV, underscoring the urgent need for the development of countermeasures. The NiV surface-displayed glycoproteins, NiV-G and NiV-F, mediate host cell attachment and fusion, respectively, and are heavily targeted by host antibodies. Here, we describe a vaccination-derived neutralizing monoclonal antibody, mAb92, that targets NiV-F. Structural characterization of the Fab region bound to NiV-F (NiV-F-Fab92) by cryo-electron microscopy analysis reveals an epitope in the DIII domain at the membrane distal apex of NiV-F, an established site of vulnerability on the NiV surface. Further, prophylactic treatment of hamsters with mAb92 offered complete protection from NiV disease, demonstrating beneficial activity of mAb92 in vivo. This work provides support for targeting NiV-F in the development of vaccines and therapeutics against NiV.IMPORTANCENipah virus (NiV) is a highly lethal henipavirus (HNV) that causes severe respiratory and neurologic disease in humans. Currently, there are no licensed vaccines or therapeutics against NiV, highlighting a need to develop countermeasures. The NiV surface displays the receptor binding protein (NiV-G, or RBP) and the fusion protein (NiV-F), which allow the virus to attach and enter cells. These proteins can be targeted by vaccines and antibodies to prevent disease. This work describes a neutralizing antibody (mAb92) that targets NiV-F. Structural characterization by cryo-electron microscopy analysis reveals where the antibody binds to NiV-F to neutralize the virus. This study also shows that prophylactic treatment of hamsters with mAb92 completely protected against developing NiV disease. This work shows how targeting NiV-F can be useful to preventing NiV disease, supporting future studies in the development of vaccines and therapeutics.
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Anticuerpos Monoclonales , Anticuerpos Neutralizantes , Anticuerpos Antivirales , Infecciones por Henipavirus , Virus Nipah , Proteínas Virales de Fusión , Virus Nipah/inmunología , Animales , Infecciones por Henipavirus/prevención & control , Infecciones por Henipavirus/inmunología , Anticuerpos Monoclonales/inmunología , Proteínas Virales de Fusión/inmunología , Proteínas Virales de Fusión/química , Anticuerpos Neutralizantes/inmunología , Anticuerpos Antivirales/inmunología , Cricetinae , Humanos , Microscopía por Crioelectrón , Epítopos/inmunología , MesocricetusRESUMEN
The mortality rate of Nipah virus (NiV) can vary in different regions, and its pattern across timelines has yet to be assessed. The primary objective is to perform a comparative analysis of mortality rates across different timelines and countries. Articles reporting NiV mortality from inception to November 2023 were analyzed in PubMed, Ovid Embase, Scopus, and Web of Science databases. A meta-analysis utilizing random-effects models determined the mortality rate secondary to NiV complications. The initial search strategy yielded 1213 records, of which 36 articles met the inclusion criteria, comprising 2736 NiV patients. The Global mortality rate of the Nipah virus in the 2014-2023 decade was 80.1% (CI: 68.7-88.1%), indicating a significant 24% increase compared to the preceding decade (2004-2013) with a mortality rate of 54.1% (CI: 35.5-71.6%). Among the countries analyzed for overall mortality from 1994-2023, India experienced the highest mortality rate at 82.7% (CI: 74.6-88.6%), followed by Bangladesh at 62.1% (CI: 45.6-76.2%), Philippines at 52.9% (CI: 30-74.5%), Malaysia at 28.9% (CI: 21.4-37.9%), and Singapore at 21% (CI: 8-45%). Subgroup analysis revealed that India consistently had the highest mortality rate for the past two decades (91.7% and 89.3%). The primary complication leading to mortality was encephalitis, accounting for 95% of cases. This systematic review and meta-analysis revealed a noteworthy surge in NiV mortality rates, particularly in the current decade (2014-2023). The escalation, with India reporting a concerning level of mortality of 89.3-91.7% in the past decades, signifies a pressing public health challenge.
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Salud Global , Infecciones por Henipavirus , Virus Nipah , Humanos , Salud Global/estadística & datos numéricos , Infecciones por Henipavirus/mortalidadRESUMEN
The henipaviruses, including Nipah virus (NiV) and Hendra virus (HeV), are biosafety level 4 (BSL-4) zoonotic pathogens that cause severe neurological and respiratory disease in humans. To study the replication machinery of these viruses, we developed robust minigenome systems that can be safely used in BSL-2 conditions. The nucleocapsid (N), phosphoprotein (P), and large protein (L) of henipaviruses are critical elements of their replication machinery and thus essential support components of the minigenome systems. Here, we tested the effects of diverse combinations of the replication support proteins on the replication capacity of the NiV and HeV minigenomes by exchanging the helper plasmids coding for these proteins among the two viruses. We demonstrate that all combinations including one or more heterologous proteins were capable of replicating both the NiV and HeV minigenomes. Sequence alignment showed identities of 92% for the N protein, 67% for P, and 87% for L. Notably, variations in amino acid residues were not concentrated in the N-P and P-L interacting regions implying that dissimilarities in amino acid composition among NiV and HeV polymerase complex proteins may not impact their interactions. The observed indiscriminate activity of NiV and HeV polymerase complex proteins is different from related viruses, which can support the replication of heterologous genomes only when the whole polymerase complex belongs to the same virus. This newly observed promiscuous property of the henipavirus polymerase complex proteins likely attributed to their conserved interaction regions could potentially be harnessed to develop universal anti-henipavirus antivirals.IMPORTANCEGiven the severity of disease induced by Hendra and Nipah viruses in humans and the continuous emergence of new henipaviruses as well as henipa-like viruses, it is necessary to conduct a more comprehensive investigation of the biology of henipaviruses and their interaction with the host. The replication of henipaviruses and the development of antiviral agents can be studied in systems that allow experiments to be performed under biosafety level 2 conditions. Here, we developed robust minigenome systems for the Nipah virus (NiV) and Hendra virus (HeV) that provide a convenient alternative for studying NiV and HeV replication. Using these systems, we demonstrate that any combination of the three polymerase complex proteins of NiV and HeV could effectively initiate the replication of both viral minigenomes, which suggests that the interaction regions of the polymerase complex proteins could be effective targets for universal and effective anti-henipavirus interventions.
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Genoma Viral , Virus Nipah , Replicación Viral , Virus Nipah/genética , Virus Nipah/fisiología , Humanos , Proteínas Virales/metabolismo , Proteínas Virales/genética , Virus Hendra/genética , Virus Hendra/metabolismo , Virus Hendra/fisiología , Animales , Henipavirus/genética , Henipavirus/metabolismo , Infecciones por Henipavirus/virología , Fosfoproteínas/metabolismo , Fosfoproteínas/genética , Proteínas de la Nucleocápside/metabolismo , Proteínas de la Nucleocápside/genética , Línea CelularRESUMEN
Langya virus (LayV) was recently detected in patients with acute pneumonic diseases in China. Genome alignment indicated that LayV is a type of zoonotic henipavirus (HNV) that might also infect domestic animals. Previous studies revealed that HNVs mainly use ephrin-B1, ephrin-B2, or ephrin-B3 as cell receptors and the attachment glycoprotein (G) is the host cell receptor-binding protein. However, the LayV receptor remains unknown. Here, we present the 2.77 Å crystal structure of the LayV G C-terminal domain (CTD). We show that the LayV G protein CTD possesses a similar architecture as the Mojiang virus (MojV) G protein but is markedly different from the Nipah virus (NiV), Hendra virus (HeV), and Cedar virus (CedV) G proteins. Surface plasmon resonance (SPR) experiments indicate that LayV G does not bind ephrin-B proteins. Steric hindrance may prevent interactions between LayV G and ephrin-B. Our data might facilitate drug development targeting LayV.
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Modelos Moleculares , Unión Proteica , Proteínas del Envoltorio Viral , Cristalografía por Rayos X , Proteínas del Envoltorio Viral/química , Proteínas del Envoltorio Viral/metabolismo , Henipavirus/metabolismo , Henipavirus/química , Humanos , Sitios de Unión , Secuencia de Aminoácidos , Dominios Proteicos , Conformación Proteica en Lámina beta , Animales , Conformación Proteica en Hélice alfaRESUMEN
The Nipah virus (NiV) and the Hendra virus (HeV) are highly pathogenic zoonotic diseases that can cause fatal infections in humans and animals. Early detection is critical for the control of NiV and HeV infections. We present the development of two antigen-detection ELISAs (AgELISAs) using the henipavirus-receptor EphrinB2 and monoclonal antibodies (mAbs) to detect NiV and HeV. The NiV AgELISA detected only NiV, whereas the NiV/HeV AgELISA detected both NiV and HeV. The diagnostic specificities of the NiV AgELISA and the NiV/HeV AgELISA were 100% and 97.8%, respectively. Both assays were specific for henipaviruses and showed no cross-reactivity with other viruses. The AgELISAs detected NiV antigen in experimental pig nasal wash samples taken at 4 days post-infection. With the combination of both AgELISAs, NiV can be differentiated from HeV. Complementing other henipavirus detection methods, these two newly developed AgELISAs can rapidly detect NiV and HeV in a large number of samples and are suitable for use in remote areas where other tests are not available.
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Anticuerpos Monoclonales , Anticuerpos Antivirales , Ensayo de Inmunoadsorción Enzimática , Efrina-B2 , Infecciones por Henipavirus , Animales , Humanos , Anticuerpos Monoclonales/inmunología , Anticuerpos Antivirales/inmunología , Antígenos Virales/inmunología , Efrina-B2/metabolismo , Virus Hendra , Infecciones por Henipavirus/diagnóstico , Virus Nipah , Receptores Virales/metabolismo , Sensibilidad y Especificidad , PorcinosRESUMEN
Henipaviruses are enveloped single-stranded, negative-sense RNA viruses of the paramyxovirus family. Two henipaviruses, Nipah virus and Hendra virus, cause a systemic respiratory and/or neurological disease in humans and ten additional species of mammals, with a high fatality rate. Because of their highly pathogenic nature, Nipah virus and Hendra virus are categorized as BSL-4 pathogens, which limits the number and scope of translational research studies on these important human pathogens. To begin to address this limitation, we are developing a BSL-2 model of authentic henipavirus infection in mice, using the non-pathogenic henipavirus, Cedar virus. Notably, wild-type mice are highly resistant to Hendra virus and Nipah virus infection. However, previous work has shown that mice lacking expression of the type I interferon receptor (IFNAR-KO mice) are susceptible to both viruses. Here, we show that luciferase-expressing recombinant Cedar virus (rCedV-luc) is also able to replicate and establish a transient infection in IFNAR-KO mice, but not in wild-type mice. Using longitudinal bioluminescence imaging (BLI) of luciferase expression, we detected rCedV-luc replication as early as 10 h post-infection. Viral replication peaks between days 1 and 3 post-infection, and declines to levels undetectable by BLI by 7 days post-infection. Immunohistochemistry is consistent with viral infection and replication in endothelial cells and other non-immune cell types within tissue parenchyma. Serology analyses demonstrate significant IgG responses to the Cedar virus surface glycoprotein with potent neutralizing activity in IFNAR-KO mice, whereas antibody responses in wild-type animals were non-significant. Overall, these data suggest that rCedV-luc infection of IFNAR-KO mice represents a viable platform for the study of in vivo henipavirus replication, anti-henipavirus host responses and henipavirus-directed therapeutics.
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We have adopted a real-time assay based on a dual-split reporter to assess cell-cell fusion mediated by the measles virus (MeV) membrane fusion machinery. This reporter system is comprised of two expression vectors, each encoding a segment of Renilla luciferase fused to a segment of GFP. To regain function, the two segments need to associate, which is dependent on cell-cell fusion between effector cells expressing the MeV fusion machinery and target cells expressing the corresponding MeV receptor. By measuring reconstituted luciferase activity, we can follow the kinetics of cell-cell fusion and quantify the extent of fusion. This assay lends itself to the study of the MeV fusion machinery comprised of the attachment and fusion glycoproteins, the matrix protein, and the MeV receptors. Moreover, entry inhibitors targeting attachment or fusion can be readily screened using this assay. Finally, this assay can be easily adopted to study the entry of other members of the Paramyxoviridae, as we have demonstrated for the henipaviruses.
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Fusión Celular , Virus del Sarampión , Internalización del Virus , Virus del Sarampión/genética , Virus del Sarampión/fisiología , Humanos , Animales , Fusión Celular/métodos , Genes Reporteros , Proteínas Fluorescentes Verdes/genética , Proteínas Fluorescentes Verdes/metabolismo , Chlorocebus aethiops , Línea Celular , Células Vero , Luciferasas de Renilla/genética , Luciferasas de Renilla/metabolismoRESUMEN
Henipavirus (HNV) is well known for two zoonotic viruses in the genus, Hendra virus (HeV) and Nipah virus (NiV), which pose serious threat to human and animal health. In August 2022, a third zoonotic virus in the genus Henipavirus, Langya virus (LayV), was discovered in China. The emergence of HeV, NiV, and LayV highlights the persistent threat of HNV to human and animal health. In addition to the above three HNVs, new species within this genus are still being discovered. Although they have not yet caused a pandemic in humans or livestock, they still have the risk of spillover as a potential threat to the health of humans and animals. It's important to understand the infection and transmission of different HNV in animals for the prevention and control of current or future HNV epidemics. Therefore, this review mainly summarizes the animal origin, animal infection and transmission of HNV that have been found worldwide, and further analyzes and summarizes the rules of infection and transmission, so as to provide a reference for relevant scientific researchers. Furthermore, it can provide a direction for epidemic prevention and control, and animal surveillance to reduce the risk of the global pandemic of HNV.
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Infecciones por Henipavirus , Henipavirus , Animales , Infecciones por Henipavirus/transmisión , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/veterinaria , Infecciones por Henipavirus/virología , Humanos , Zoonosis/transmisión , Zoonosis/virología , Zoonosis Virales/transmisión , Zoonosis Virales/virología , Virus Nipah/patogenicidad , Virus HendraRESUMEN
Langya virus (LayV) is a recently discovered henipavirus (HNV), isolated from febrile patients in China. HNV entry into host cells is mediated by the attachment (G) and fusion (F) glycoproteins which are the main targets of neutralizing antibodies. We show here that the LayV F and G glycoproteins promote membrane fusion with human, mouse, and hamster target cells using a different, yet unknown, receptor than Nipah virus (NiV) and Hendra virus (HeV) and that NiV- and HeV-elicited monoclonal and polyclonal antibodies do not cross-react with LayV F and G. We determined cryoelectron microscopy structures of LayV F, in the prefusion and postfusion states, and of LayV G, revealing their conformational landscape and distinct antigenicity relative to NiV and HeV. We computationally designed stabilized LayV G constructs and demonstrate the generalizability of an HNV F prefusion-stabilization strategy. Our data will support the development of vaccines and therapeutics against LayV and closely related HNVs.
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Virus Hendra , Infecciones por Henipavirus , Henipavirus , Virus Nipah , Humanos , Animales , Ratones , Microscopía por Crioelectrón , Glicoproteínas , Internalización del VirusRESUMEN
Nipah virus (NiV) is a highly lethal, zoonotic Henipavirus (HNV) that causes respiratory and neurological signs and symptoms in humans. Similar to other paramyxoviruses, HNVs mediate entry into host cells through the concerted actions of two surface glycoproteins: a receptor-binding protein (RBP) that mediates attachment and a fusion glycoprotein (F) that triggers fusion in an RBP-dependent manner. NiV uses ephrin-B2 (EFNB2) and ephrin-B3 (EFNB3) as entry receptors. Ghana virus (GhV), a novel HNV identified in a Ghanaian bat, uses EFNB2 but not EFNB3. In this study, we employ a structure-informed approach to identify receptor-interfacing residues and systematically introduce GhV-RBP residues into a NiV-RBP backbone to uncover the molecular determinants of EFNB3 usage. We reveal two regions that severely impair EFNB3 binding by NiV-RBP and EFNB3-mediated entry by NiV pseudotyped viral particles. Further analyses uncovered two-point mutations (NiVN557SGhV and NiVY581TGhV) pivotal for this phenotype. Moreover, we identify NiV interaction with Y120 of EFNB3 as important for the usage of this receptor. Beyond these EFNB3-related findings, we reveal two domains that restrict GhV binding of EFNB2, confirm the HNV-head as an immunodominant target for polyclonal and monoclonal antibodies, and describe putative epitopes for GhV- and NiV-specific monoclonal antibodies. Cumulatively, the work presented here generates useful reagents and tools that shed insight to residues important for NiV usage of EFNB3, reveal regions critical for GhV binding of EFNB2, and describe putative HNV antibody-binding epitopes. IMPORTANCE: Hendra virus and Nipah virus (NiV) are lethal, zoonotic Henipaviruses (HNVs) that cause respiratory and neurological clinical features in humans. Since their initial outbreaks in the 1990s, several novel HNVs have been discovered worldwide, including Ghana virus. Additionally, there is serological evidence of zoonotic transmission, lending way to concerns about future outbreaks. HNV infection of cells is mediated by the receptor-binding protein (RBP) and the Fusion protein (F). The work presented here identifies NiV RBP amino acids important for the usage of ephrin-B3 (EFNB3), a receptor highly expressed in neurons and predicted to be important for neurological clinical features caused by NiV. This study also characterizes epitopes recognized by antibodies against divergent HNV RBPs. Together, this sheds insight to amino acids critical for HNV receptor usage and antibody binding, which is valuable for future studies investigating determinants of viral pathogenesis and developing antibody therapies.
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Infecciones por Henipavirus , Henipavirus , Receptores Virales , Humanos , Aminoácidos/genética , Anticuerpos Monoclonales/metabolismo , Proteínas Portadoras/metabolismo , Efrina-B3/genética , Efrina-B3/química , Efrina-B3/metabolismo , Epítopos/genética , Epítopos/metabolismo , Ghana , Virus Hendra/metabolismo , Henipavirus/clasificación , Henipavirus/genética , Henipavirus/metabolismo , Mutagénesis , Virus Nipah/metabolismo , Proteínas del Envoltorio Viral/genética , Internalización del Virus , Receptores Virales/metabolismoRESUMEN
Nipah virus (NiV) has been recently ranked by the World Health Organization as being among the top eight emerging pathogens likely to cause major epidemics, whereas no therapeutics or vaccines have yet been approved. We report a method to deliver immunogenic epitopes from NiV through the targeting of the CD40 receptor of antigen-presenting cells by fusing a selected humanized anti-CD40 monoclonal antibody to the Nipah glycoprotein with conserved NiV fusion and nucleocapsid peptides. In the African green monkey model, CD40.NiV induces specific immunoglobulin A (IgA) and IgG as well as cross-neutralizing responses against circulating NiV strains and Hendra virus and T cell responses. Challenge experiments using a NiV-B strain demonstrate the high protective efficacy of the vaccine, with all vaccinated animals surviving and showing no significant clinical signs or virus replication, suggesting that the CD40.NiV vaccine conferred sterilizing immunity. Overall, results obtained with the CD40.NiV vaccine are highly promising in terms of the breadth and efficacy against NiV.
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Vacunas Virales , Animales , Chlorocebus aethiops , Linfocitos T , Formación de Anticuerpos , Células Presentadoras de Antígenos , Replicación ViralRESUMEN
Henipaviruses are a genus of emerging pathogens that includes the highly virulent Nipah and Hendra viruses that cause reoccurring outbreaks of disease. Henipaviruses rely on two surface glycoproteins, known as the attachment and fusion proteins, to facilitate entry into host cells. As new and divergent members of the genus have been discovered and structurally characterized, key differences and similarities have been noted. This review surveys the available structural information on Henipavirus glycoproteins, complementing this with information from related biophysical and structural studies of the broader Paramyxoviridae family of which Henipaviruses are members. The process of viral entry is a primary focus for vaccine and drug development, and this review aims to identify critical knowledge gaps in our understanding of the mechanisms that drive Henipavirus fusion.
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Virus Hendra , Infecciones por Henipavirus , Henipavirus , Virus Nipah , Humanos , Infecciones por Henipavirus/epidemiología , Glicoproteínas/metabolismoRESUMEN
First reported in August 2022, the Langya virus (LayV) has emerged as a potential global health threat in the post-COVID-19 era. Preliminary reports show that 35 patients near Shandong and Henan, China experienced a febrile acute LayV infection. We conducted this review following the PRISMA protocol to synthesise current knowledge on LayV's characteristics in terms of molecular, clinical, and public health perspectives. This virus belongs to the Paramyxoviridae family and carries a non-segmented, single-stranded negative-sense RNA genome. Shrews may be the natural reservoir of the virus. Clinical symptoms range from mild flu-like symptoms to severe manifestations involving pneumonia, haematological disorders, and organ dysfunction. Diagnostic methods include PCR and ELISA assays. Despite the absence of established treatments, antiviral drugs such as ribavirin and chloroquine may be useful in some cases. In light of prevention, a comprehensive approach that emphasises multidisciplinary collaboration is crucial for early surveillance and response. Urgent global efforts are needed for vaccine development and preparedness against this potential pandemic threat. As the viral dynamics remain uncertain, a proactive approach is vital to mitigate the impact of not only LayV but also future threats on a large scale in long term.
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COVID-19 , Henipavirus , Zoonosis , Animales , Humanos , Zoonosis/epidemiología , Zoonosis/prevención & control , SARS-CoV-2 , Antivirales/uso terapéuticoRESUMEN
Nipah virus Bangladesh (NiVB) is a bat-borne zoonosis transmitted between people through the respiratory route. The risk posed by related henipaviruses, including Hendra virus (HeV) and Nipah virus Malaysia (NiVM), is less clear. We conducted a broad search of the literature encompassing both human infections and animal models to synthesize evidence about potential for person-to-person spread. More than 600 human infections have been reported in the literature, but information on viral shedding was only available for 40 case-patients. There is substantial evidence demonstrating person-to-person transmission of NiVB, and some evidence for NiVM. Less direct evidence is available about the risk for person-to-person transmission of HeV, but animals infected with HeV shed more virus in the respiratory tract than those infected with NiVM, suggesting potential for transmission. As the group of known henipaviruses continues to grow, shared protocols for conducting and reporting from human investigations and animal experiments are urgently needed.
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Virus Hendra , Infecciones por Henipavirus , Virus Nipah , Animales , Humanos , Infecciones por Henipavirus/transmisión , Malasia , Zoonosis/transmisiónRESUMEN
Henipaviruses are zoonotic viruses, including some highly pathogenic and capable of serious disease and high fatality rates in both animals and humans. Hendra virus and Nipah virus are the most notable henipaviruses, resulting in significant outbreaks across South Asia, South-East Asia, and Australia. Pteropid fruit bats have been identified as key zoonotic reservoirs; however, the increased discovery of henipaviruses outside the geographic distribution of Pteropid fruit bats and the detection of novel henipa-like viruses in other species such as the shrew, rat, and opossum suggest that Pteropid bats are not the sole reservoir for henipaviruses. In this review, we provide an update on henipavirus spillover events and describe the recent detection of novel unclassified henipaviruses, with a strong focus on the shrew and its emerging role as a key host of henipaviruses.
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Quirópteros , Virus Hendra , Infecciones por Henipavirus , Virus Nipah , Humanos , Animales , Ratas , Infecciones por Henipavirus/epidemiología , Infecciones por Henipavirus/veterinaria , MusarañasRESUMEN
Introduction: The Eidolon helvum fruit bat is one of the most widely distributed fruit bats in Africa and known to be a reservoir for several pathogenic viruses that can cause disease in animals and humans. To assess the risk of zoonotic spillover, we conducted a serological survey of 304 serum samples from E. helvum bats that were captured for human consumption in Makurdi, Nigeria. Methods: Using pseudotyped viruses, we screened 304 serum samples for neutralizing antibodies against viruses from the Coronaviridae, Filoviridae, Orthomyxoviridae and Paramyxoviridae families. Results: We report the presence of neutralizing antibodies against henipavirus lineage GH-M74a virus (odds ratio 6.23; p < 0.001), Nipah virus (odds ratio 4.04; p = 0.00031), bat influenza H17N10 virus (odds ratio 7.25; p < 0.001) and no significant association with Ebola virus (odds ratio 0.56; p = 0.375) in this bat cohort. Conclusion: The data suggest a potential risk of zoonotic spillover including the possible circulation of highly pathogenic viruses in E. helvum populations. These findings highlight the importance of maintaining sero-surveillance of E. helvum, and the necessity for further, more comprehensive investigations to monitor changes in virus prevalence, distribution over time, and across different geographic locations.