Detection of a #Merbecovirus with potential #ACE2 usage in #France

 

ABSTRACT

A novel Merbecovirus, designated Cam-2023, has been identified in Pipistrellus pipistrellus in France through non-invasive surveillance. Phylogenetic analysis demonstrates that Cam-2023 belongs to a Merbecovirus clade previously associated with ACE2 usage in closely related viruses detected in the Netherlands and Russia. While the receptor usage of Cam-2023 remains to be functionally validated, sequence similarities within the Spike protein, particularly the receptor-binding domain, suggest a putative association with a Merbecovirus clade previously associated with ACE2 usage. This discovery broadens the known host diversity of this lineage and extends its geographical range to Western Europe. Our findings highlight the importance of continuous surveillance in European bat populations to better characterize the distribution and zoonotic potential of such high-risk coronaviruses.

Source: 

Link: https://www.tandfonline.com/doi/full/10.1080/22221751.2026.2651469

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Heart-nosed #bat #alphacoronaviruses use #human CEACAM6 to enter #cells

 

Abstract

Identifying viruses with zoonotic potential on the basis of their ability to enter human cells is a critical component of pandemic prediction, prevention and preparedness. Here using a computational approach that retains maximum phylogenetic diversity, we selected an optimal subset of alphacoronavirus spike proteins to screen against broad coronavirus receptor libraries. Most of the selected spike proteins did not use any of the established coronavirus receptors. However, the pseudotyped spike protein of Cardioderma cor (heart-nosed bat) coronavirus KY43 (CcCoV-KY43) could enter human cells. Using a recombinant CcCoV receptor-binding domain (RBD) and a human receptor screening platform, we identified direct interactions with the human CEACAM proteins CEACAM3, CEACAM5 and CEACAM6. Overexpression of human CEACAM6—a protein widely expressed in the human lung—conferred permissivity to otherwise refractory human cells. A crystal structure showed that the RBD binds the amino-terminal IgV-like domain of human CEACAM6. Immune surveillance studies using sera of individuals from the Taveta region of Kenya, where CcCoV-KY43 was identified, did not show significant evidence of recent spillover. Wider characterization of alphacoronaviruses related to CcCoV-KY43 showed that human CEACAM6 is used by two other CcCoVs collected in Kenya. Moreover, there was more restricted nonhuman CEACAM6 tropism for viruses isolated from Rhinolophus bats from Russia and China. Thus, alphacoronaviruses that use CEACAM6 are probably geographically widespread, and viruses from East Africa show potential for transmission to humans.

Source: 

Link: https://www.nature.com/articles/s41586-026-10394-x

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The #Mengla virus (Filoviridae: #Dianlovirus)

 

Abstract

Introduction. 

Filoviruses associated with various species of pteropodid bats (Chiroptera: Pteropodidae) are traditionally regarded as potential causative agents of hemorrhagic fevers with epidemic potential. The known agents of Ebola and Marburg fevers periodically cause sporadic cases and epidemic outbreaks in African countries. Recent discoveries of novel filoviruses associated with pteropodid bats in South and Southeast Asia highlight the necessity to investigate their genetic diversity and pathogenic potential.

The aim of this study was to investigate the genetic diversity and pathogenic potential of new filoviruses associated with bats, based on literature data.

Materials and methods. 

This review is based on an analysis of published literature describing the detection and molecular characterization of novel filoviruses identified in different geographic regions, with a particular focus on filoviruses associated with pteropodid bats in South and Southeast Asia. The analyzed studies include data on virus discovery, genome organization, taxonomic classification, and experimental assessment of biological properties. 

Results. 

Several novel filoviruses have been identified by metagenomic RNA sequencing of tissues from pteropodid bats captured in South and Southeast Asia. Among them, Mengla virus was detected in tissues of pteropodid bats (Rousettus spp.) captured in Mengla County, Yunnan Province, People’s Republic of China. Owing to a high level of genetic divergence, Mengla virus was classified as a representative of a new genus, Dianlovirus, within the family Filoviridae. Although a live isolate of Mengla virus has not yet been obtained, experimental studies using chimeric minigenome systems and virus-like particles suggest that the virus may exhibit tropism for tissues of various vertebrate hosts, including humans.

Conclusion. 

Members of the family Filoviridae are widely distributed within the geographic range of their natural reservoir–pteropodid bats–across South and Southeast Asia, including viruses evolutionarily related to Ebola and Marburg viruses. Although human disease caused by Mengla virus and other recently discovered filoviruses has not been documented, the potential for cross-species transmission and the emergence of novel filovirus infections in endemic regions remains.

Source: 

Link: https://virusjour.crie.ru/jour/article/view/16805

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Paralytic #rabies #outbreak mimicking #GBS in French #Amazonia

 

Abstract

Background

In the Amazonian region, vampire bats are the primary reservoir of rabies virus, causing sporadic and lethal human rabies cases that often remain unnoticed. Managing human cases in this region is challenging and further complicated by atypical clinical forms and the potential exposure to various toxic compounds, particularly among gold miners.

Methods

We carried out clinical, electrical, biological and histological analysis of concurrent cases of progressive motor neuronopathy and fatal encephalitis in a context of regular exposure to bat bites of gold miners living in a small and remote gold mine camp in Amazonia, in French Guiana, South America.

Findings

We analyzed a spatio-temporal cluster of three suspected rabies cases in 2024 with a fatal outcome, with concomitant onset of acute bilateral lower-limb paralysis without demyelination, two of which occurred presumably two weeks after a bat-bite. Electroneuromyography suggested the involvement of the anterior horn of the spinal cord, as described in furious forms of rabies. None of the cases exhibited other cardinal signs of the furious form. Confirmation of rabies was obtained for them on sera and brain biopsies collected ante- and post-mortem respectively.

Interpretation

The concurrent occurrence of disease, the axonal motor neuropathy mimicking the motor form of Guillain Barré syndrome in the context of paralytic rabies, lead to diagnostic-wandering. This underscores the importance of thinking about vampire bat rabies virus in the presence of any atypical neurological picture in patients living in exposed areas in Latin America.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014149

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Three decades of #discovery: An overview of #Hendra virus, the original #Henipavirus

 

Abstract

Hendra virus (HeV) emerged in Australia in 1994, causing a devastating outbreak among horses in Brisbane with spread to humans, resulting in one death. This nonsegmented, negative-stranded RNA virus belongs to the family Paramyxoviridae and represents the first zoonotic paramyxovirus isolated from bats. Flying foxes (genus Pteropus) serve as the natural reservoir, with all four mainland Australian species carrying antibodies with no apparent disease. HeV initiates infection by binding ephrin-B2 receptors on vascular endothelial cells, driving characteristic pathology involving vasculitis, thrombosis, and neurological complications. Horses are amplifying hosts, shedding virus abundantly in respiratory secretions and posing transmission risks to humans during invasive procedures. To date, seven confirmed human infections have been documented, with a 57% fatality rate, presenting as severe respiratory disease or progressive encephalitis. Two genetic variants are now recognized: the original HeV genotype 1 and the emerging HeV genotype 2, identified in limited equine cases. Recent surveillance of bat roosts revealed substantial viral diversity, with peak shedding occurring during winter—coinciding with equine spillover peaks. Prevention integrates multiple strategies: the licensed equine vaccine Equivac which provides One Health protection for both horses and human contacts; biosecurity measures including proper PPE; and habitat restoration to reduce nutritional stress in bat populations. Emerging therapeutics include monoclonal antibodies, with m102.4 showing cross-protective activity against both HeV and the closely related Nipah virus. No licensed human vaccines currently exist, though candidates are in development. Future prevention strategies increasingly recognize the importance of Indigenous-led conservation approaches alongside biomedical interventions. This review will focus on the history of HeV, virus replication and diversity, epidemiology, clinical manifestations, diagnosis, treatment, prevention, as well as ecological and interdisciplinary countermeasures.

Author summary

Hendra virus (HeV) was first detected in 1994, with two outbreaks occurring within 2 months of that year. One was the index outbreak in the Brisbane suburb of Hendra, and the other was retrospectively diagnosed in the following year. This review examines the discoveries that have been made in the 30 years since its discovery.

Source: 

Link: https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0014138

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Genetic diversity of alpha and #betacoronaviruses in cave and temple-roosting #bats in #Vientiane Province, #Lao PDR

 

Abstract

The emergence of MERS-CoV, SARS-CoV-1, and SARS-CoV-2 highlights the significant public health and economic threats posed by coronaviruses. In Lao PDR, SARS-CoV-2-related bat coronaviruses capable of binding to human ACE2 receptors have been found in northern regions, but little is known about coronavirus diversity in anthropized environments like temples. This study investigated coronavirus circulation, diversity, and prevalence in bats from caves and temples in Vientiane Province, Lao PDR. A total of 648 guano samples (505 Chaerephon plicatus, 100 Hipposideros spp., 43 Taphozous spp.) were collected between December 2022 and June 2023 and screened using pan-coronavirus RT-PCR approach. The overall positivity rate was 17.28%, significantly higher in caves (18.8%) than temples (4.41%) (p = 0.003). C. plicatus showed the highest positivity rate (21.38%), followed by Hipposideros spp. 4%, while Taphozous spp. were negative. Phylogenetic analysis revealed diverse coronavirus lineages within Alphacoronavirus (80.4%) and Betacoronavirus (19.6%) genera. Although none were closely related to known human pathogens, coronaviruses of Decacovirus genus related to Chinese bat viruses and Pedacovirus genus similar to porcine epidemic diarrhea virus (PEDV) were detected. Unclassified betacoronaviruses identified were also related to viruses from C. plicatus in Thailand. This study provides valuable insights into coronavirus circulation in both natural and anthropized environments. The detection of PEDV-like viruses underlines the need for continued surveillance at the human-bat interface, where activities like guano harvesting and temple visits increase contacts. Further genomic and functional studies would enhance our understanding of their evolutionary relationships and potential for further cross-species transmission.

Source: 

Link: https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0341737

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Swine acute #diarrhea syndrome #coronavirus-related viruses from #bats show potential #interspecies infection

 

ABSTRACT

Swine acute diarrhea syndrome coronavirus (SADS-CoV) is a bat-originated virus causing severe diseases in piglets. Since the 2016 outbreak, diverse SADS-related CoVs (SADSr-CoVs) have been detected in Rhinolophus bats in China and Southeast Asia, but their potential interspecies infection and pathogenicity remain unknown. Herein, we sequenced the spike (S) genes of bat SADSr-CoVs and classified them into four genotypes. We constructed an infectious SADS-CoV cDNA clone (rSADS-CoV) and nine recombinant viruses by replacing the SADS-CoV S gene with that of bat SADSr-CoVs. Recombinant SADSr-CoVs could replicate efficiently in respiratory and intestinal cell lines and human- and swine-derived organoids and caused varying tissue damage and mortality in suckling mice. These viruses can be classified into at least five serotypes based on cross-neutralization assays. Our findings highlight the potential risk of interspecies infection and provide important information for future surveillance of these bat viruses.

Source: Journal of Virology, https://journals.asm.org/doi/full/10.1128/jvi.02240-24?af=R

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#Spillover of #H5 #influenza viruses to vampire #bats at the marine-terrestrial interface

 

Abstract

The highly pathogenic H5N1 avian influenza A virus (IAV) clade 2.3.4.4b has spread globally and spilled over into multiple mammalian species, raising concerns about its pandemic potential. In late 2022, clade 2.3.4.4b viruses devastated seabird and marine mammal populations along the Pacific coast of South America. Here, we report the first evidence of H5 IAV infections in wild bats globally, focusing on common vampire bats (Desmodus rotundus) in coastal areas of Peru. Longitudinal serological screening, stable isotope analysis and metabarcoding revealed repeated exposures to H5 IAVs in vampire bats which feed on coastal wildlife species heavily impacted by the 2.3.4.4b epizootic, but no evidence of infection in populations without access to marine prey. We further report bat gene flow between IAV-exposed and IAV-naive populations, and IAV infections in a vampire bat colony that fed on both marine and terrestrial livestock prey, providing insights into how future IAV epizootics might spread spatially within bats and between marine and terrestrial ecosystems if a bat reservoir were established. Immunohistochemistry demonstrated that the H5 haemagglutinin protein binds to the upper respiratory tract of vampire bats, suggesting bat tissue susceptibility to H5 IAVs. Finally, vampire bat-derived kidney, liver, and lung cells supported entry, replication, and egress of avian and mammalian 2.3.4.4b viruses, confirming cellular infectivity. These results illustrate how combining ecological inference and experimental virology can pinpoint the species origins and biological significance of viral spillover at species interfaces. Recurrent exposures from marine wildlife, tissue and cellular susceptibility to H5N1 IAVs, and connections to other IAV-susceptible terrestrial mammals establish the prerequisite conditions for vampire bats to spread IAVs between marine and terrestrial environments or to form a novel reservoir of highly pathogenic IAVs.

Competing Interest Statement

The authors have declared no competing interest.

Funder Information Declared

Wellcome Trust, https://ror.org/029chgv08, 218518/Z/19/Z, 217221/Z/19/Z, CC1114

Medical Research Council, MC_UU_00034/3, CC1114

NSF/Biotechnology and Biological Sciences Research Council, DEB 2011069, BB/V003798/1, BB/V004697/1

Medical Research Council and Department for Environment Food and Rural Affairs (FluTrailMap-One Health), MR/Y03368X/1, BB/Y007298/1

NERC, NE/V014730/1

Biotechnology and Biological Sciences Research Council/Medical Research Council, BB/Y006879/1

Carlsberg Foundation, https://ror.org/01kpjmx04, CF21-0411

Villum Fonden, VIL41390

Francis Crick Institute, Cancer Research UK, CC1114

National Institute of Allergy and Infectious Diseases, https://ror.org/043z4tv69, 75N93021C00015

Source: BioRxIV, https://www.biorxiv.org/content/10.1101/2025.11.09.686930v1

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Detection and genetic characterization of #alphacoronaviruses in co-roosting #bat species, southeastern #Kenya

 

Abstract

Bats are associated with some of the most significant and virulent emerging zoonoses globally, yet research and surveillance of bat pathogens remains limited across parts of the world. We surveyed the prevalence and genetic diversity of coronaviruses from bats in Taita Hills, southeastern Kenya, as part of ongoing surveillance efforts in this remote part of eastern Africa. We collected fecal and intestinal samples in May 2018 and March 2019 from 16 bat species. We detected one genus of coronavirus (alphacoronavirus), with an overall RNA prevalence of 6.5% (30/463). The prevalence of coronavirus RNA was 3.8% (9/235) and 11.6% (21/181) for the two most captured free-tailed bat species, Mops condylurus and M. pumilus respectively, with no detections from other bat species (0/90). Phylogenetic analyses based on the partial RNA-dependent RNA polymerase gene and whole genome sequences revealed that the sequences clustered together and were closely related to alphacoronavirus detected in free tailed bats in Eswatini, Nigeria and Rhinolophus simulator bats in South Africa. The sequences were more distantly related to alphacoronavirus isolated from Chaerophon plicatus bat species in Yunnan province, China and Ozimops species from southwestern Australia. These findings highlight coronavirus transmission among bats that share habitats with humans and livestock, posing a potential risk of exposure. Future research should investigate whether coronaviruses detected in these bats have the potential to spillover to other hosts.

Author summary

Bats are known to carry several zoonotic pathogens with potential to cause serious illnesses and death in humans. Yet, surveillance on the pathogens they carry remains limited in much of the world. We studied the prevalence and diversity of coronaviruses from bats in Taita Hills, southeastern Kenya to better understand the circulation of these viruses and inform disease preparedness. We detected alphacoronaviruses in urban Mops condylurus and M. pumilus bat species. The bat alpha coronaviruses we detected were closely related to alphacoronaviruses that have been previously detected in bats elsewhere in Africa and distantly related to alphacoronavirus detected from Chaerophon plicatus bat species in Yunnan province, China and Ozimops species from southwestern Australia. This work demonstrates coronavirus circulation among bats that share habitats with people and livestock providing conditions that can lead to spillover. Identifying whether coronaviruses detected in these bats have the potential to infect other hosts is critical for developing countermeasures and mitigating potential outbreaks.

Source: PLoS Neglected Tropical Diseases, https://journals.plos.org/plosntds/article?id=10.1371/journal.pntd.0012805

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HKU25 clade #MERS-related #coronaviruses use #ACE2 as a functional #receptor

 

Abstract

Dipeptidyl peptidase-4 (DPP4) is an established receptor for Middle East respiratory syndrome-related coronaviruses (MERSr-CoVs), while recent studies have identified angiotensin-converting enzyme 2 (ACE2) usage in multiple merbecovirus clades. Yet, receptor usage of many genetically diverse bat MERSr-CoVs remains unclear. Here we show that broadly distributed HKU25 clade merbecoviruses use ACE2, rather than DPP4, as their receptor. Cryo-electron microscopy revealed that HsItaly2011 and VsCoV-a7 strains engage ACE2 similarly to HKU5 but with remodelled interfaces and distinct orthologue selectivity, suggesting a shared evolutionary origin of ACE2 recognition. EjCoV-3, a close relative of the DPP4-using BtCoV422, showed broad multi-species ACE2 tropism and preadaptation to human ACE2. Several ACE2 glycans and residues within or near the binding interface were identified as determinants of orthologue selectivity. These viruses remain sensitive to several broadly neutralizing antibodies and entry inhibitors, indicating potential countermeasures for future outbreaks. These findings highlight the versatility of ACE2 as a functional receptor for diverse coronaviruses.

Source: Nature Microbiology, https://www.nature.com/articles/s41564-025-02152-y

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#Bat #sarbecovirus WIV1-CoV bears an adaptive #mutation that alters #spike dynamics and enhances #ACE2 binding

 

Abstract

SARS-like betacoronaviruses (sarbecoviruses) endemic in bats pose a significant zoonotic threat to humans. Genetic pathways associated with spillover of bat sarbecoviruses into humans are incompletely understood. We previously showed that the wild-type spike of the rhinolophid bat coronavirus SHC014-CoV has poor entry activity and uncovered two distinct genetic pathways outside the receptor-binding domain (RBD) that increased spike opening, ACE2 binding, and cell entry. Herein, we show that the widely studied bat sarbecovirus WIV1-CoV is likely a cell culture-adapted variant whose progenitor bears a spike resembling that of Rs3367-CoV, which was sequenced from the same population of rhinolophid bats as SHC014-CoV. Our findings suggest that the acquisition of a single amino-acid substitution in the ‘630-loop’ of the S1 subunit was the key spike adaptation event during the successful isolation of WIV1-CoV, and that it enhances spike opening, virus-receptor recognition, and cell entry in much the same manner as the substitutions we previously identified in SHC014-CoV using a pseudotype system. The conformational constraints on both the SHC014-CoV and Rs3367-CoV spikes could be alleviated by pre-cleaving them with trypsin, suggesting that the spike-opening substitutions arose to circumvent the lack of S1–S2 cleavage. We propose that the ‘locked-down’ nature of these spikes and their requirement for S1–S2 cleavage to engage ACE2 represent viral optimizations for a fecal-oral lifestyle and immune evasion in their natural hosts. These adaptations may be a broader property of bat sarbecoviruses than currently recognized. The acquisition of a polybasic furin cleavage site at the S1–S2 boundary is accepted as a key viral adaptation for SARS-CoV-2 emergence that overcame a host protease barrier to viral entry in the mammalian respiratory tract. Our results suggest alternative spillover scenarios in which spike-opening substitutions that promote virus-receptor binding and entry could precede, or even initially replace, substitutions that enhance spike cleavage in the zoonotic host.

Source: PLoS Pathogens, https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1013123

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First #Evidence of #Mammarenavirus in the Giant Fruit #Bat (Artibeus lituratus) in #Mexico

 

Abstract

Background: 

In Mexico, two Mammarenavirus genotypes have been identified: Real de Catorce virus and Ocozocoautla de Espinosa virus (OCEV), which are found in rodents (Neotoma leucodon and Peromyscus mexicanus). Mammarenaviruses from clade B cause mild to severe infectious diseases in humans, particularly in South America. A 1967 outbreak in Chiapas, Mexico, was potentially linked to the OCEV.

Materials and Methods: 

Between 2017 and 2020, we collected bats across southern/southeastern Mexico to identify Mammarenavirus reservoirs. We analyzed 81 liver samples from 14 bat species using nested PCR. For quality control, we synthesized and OCEV S-region fragment into an ampicillin-resistant pUC57 plasmid, cloned in One Shot Stbl3 chemically competent E. coli.

Results: 

Here, we report the first detection of a Mammarenavirus (OCEV) in an Artibeus lituratus bat from Sabancuy, Campeche, southeastern Mexico. This finding represents the third Mammarenavirus recorded in this bat species in the Americas, suggesting it may harbor multiple Mammarenavirus species (OCEV and Mammarenavirus tacaribeense).

Conclusions: 

While this represents the first documentation of OCEV in a bat, it remains unknown whether environmental stressors could facilitate potential transmission to humans, particularly given the close association between Artibeus bats and human populations.

Source: Vector-Borne and Zoonotic Diseases, https://www.liebertpub.com/doi/abs/10.1177/15303667251377563

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Novel #Henipavirus, Salt Gully Virus, Isolated from Pteropid #Bats, #Australia

 

Abstract

We describe isolation and characterization of a novel henipavirus, designated Salt Gully virus, from the urine of pteropid bats in Australia. We noted the virus to be most closely related to Angavokely virus, not reliant on ephrin receptors for cell entry, and of unknown risk for human disease.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/9/25-0470_article

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Diversity and #spillover #risk of swine acute diarrhea syndrome and related #coronaviruses in #China and Southeast #Asia

 

ABSTRACT

Bats are the reservoir hosts of emerging coronaviruses (CoVs) affecting human and livestock health. We assessed the diversity, evolution, and geographic distribution of two alphacoronaviruses (subgenus Rhinacovirus) with considerable potential for emergence: swine acute diarrhea syndrome coronavirus (SADS-CoV), which has caused large outbreaks in pigs in China and can infect primary human airway epithelial cells in vitro; and the related Rhinolophus bat coronavirus HKU2 (HKU2-CoV). Phylogenetic analyses of 523 rhinacovirus sequences from bats in China and Southeast Asia suggest these viruses should be reclassified into at least two distinct CoV species representing two well-supported monophyletic clades. Stronger phylogenetic clustering by sampling location than by host species suggests infrequent long-distance transmission of rhinacoviruses in southern China. Ancestral state reconstruction analysis indicates that R. sinicus/thomasi and R. affinis have played an important role in rhinacovirus evolution in southern China and that R. affinis is the likely reservoir host of SADS-CoV that spilled over into pigs. We used species distribution modeling of Rhinolophus spp. bat hosts of rhinacoviruses, combined with pig and human density data, to identify potential geographic rhinacovirus spillover risk in Southeast Asia. Areas of high pig density within suitable bat habitat exist primarily in southern China and northern Vietnam, and hotspots of the highest human density within suitable bat habitat are primarily along the southern coast of China, Java, and central Thailand. Targeted surveillance of pigs and people in these regions may facilitate the timely detection of bat CoV spillover events and mitigate the risk of future outbreaks.

IMPORTANCE

Bats are the reservoir or ancestral hosts of important emerging coronaviruses affecting people (e.g., SARS-CoV and SARS-CoV-2) and livestock (e.g., PEDV, SADS-CoV). Here, we analyzed 523 genetic sequences of SADS-CoV that caused large-scale die-offs of pigs in China, which is known to be able to infect human cells and related HKU2-CoVs. We used this information to identify the horseshoe bat Rhinolophus affinis as the likely spillover host for the outbreak in pigs, and identified the bat species within which these viruses evolved. We then modeled the distribution of these host species and their overlap with dense human and pig populations to identify the regions where surveillance programs can help identify spillover events and prevent future outbreaks.

Source: mBio, https://journals.asm.org/doi/full/10.1128/mbio.01197-24?af=R

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Characterization of a #MERS-related #betacoronavirus in Danish brown long-eared #bats (Plecotus auritus)

 

Abstract

Background

Bats are recognized as natural reservoir hosts for numerous viruses and are believed to be the evolutionary origin of alpha- and beta-coronaviruses (CoVs), such as SARS-CoV, SARS-CoV-2, and possibly MERS-CoV. MERS-related beta-CoVs have been identified in bat species from Africa, America, Asia, and Europe. In this study, we describe the first detection and characterization of a MERS-related beta-CoV in Danish brown long-eared bats (Plecotus auritus).

Methods

Fecal samples collected through a national surveillance program were screened using pan-CoV RT-qPCRs. Positive samples underwent ORF1b sequencing, microarray analysis and Illumina MiSeq sequencing, followed by metagenomic assembly of full-length genomes. A global phylogenetic tree was used to determine placement within the Coronaviridae family and local maximum likelihood phylogenetic analysis clarified subgroup placement. The receptor-binding potential of the spike protein to human DPP4, ACE2, and bat ACE2 orthologs was assessed through phylogenetic analysis of the receptor-binding domain (RBD), alongside homology modeling and structural analysis.

Results

Three samples tested positive for CoVs. One sample from a Soprano pipistrelle (Pipistrellus pygmaeus) was identified as alpha-CoV by ORF1b sequencing. The remaining two samples, obtained from a colony of Plecotus auritus, were identified as beta-CoVs, and separate microarray results indicated the presence of a MERS-related CoV. Full genomes were successfully assembled using a metagenomic approach. Phylogenetic analysis placed them within the merbecoviruses, forming a distinct clade with viruses detected in Vespertilionidae bats from Western Europe and East Asia. Analysis of the RBD placed them within the HKU25 clade. Structural modeling suggested hydrogen bonding patterns between the RBD and human/bat ACE2 orthologs or human DPP4, similar to known in vitro complexes, indicating potential receptor binding.

Conclusion

This is the first report of MERS-related beta-CoVs in bats from Denmark. Phylogenetic analyses reveal that these novel viruses belong to the HKU25 clade, a clade with known ACE2 receptor preference. Experimental validation is needed to confirm the receptor-binding potential, as additional interactions at the RBD-receptor interface may differ from previously described bat-merbecoviruses. Continued surveillance is crucial to identify potential intermediate hosts and assess interspecies transmission risk, with focus on the spike protein, receptor specificity, and binding affinity.

Source: Virology Journal, https://virologyj.biomedcentral.com/articles/10.1186/s12985-025-02883-8

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Identification and characterization of novel #bat #coronaviruses in #Spain

Abstract

The zoonotic transmission of bat coronaviruses poses a threat to human health. However, the diversity of bat-borne coronaviruses remains poorly characterized in many geographical areas. Here, we recovered eight coronavirus genomes by performing a metagenomic analysis of fecal samples from hundreds of individual bats captured in Spain, a country with high bat diversity. Three of these genomes corresponded to potentially novel coronavirus species belonging to the alphacoronavirus genus. Phylogenetic analyses revealed that some of these viruses are closely related to coronaviruses previously described in bats from other countries, suggesting a shared viral reservoir worldwide. Using viral pseudotypes, we investigated the receptor usage of the identified viruses and found that one of them can use human ACE2, albeit with lower affinity than SARS-CoV-2. However, the receptor usage of the other viruses remains unknown. This study broadens our understanding of coronavirus diversity and identifies research priorities for the prevention of zoonotic viral outbreaks.

Author summary

Bats carry many different viruses, some of which can infect humans. Among these, bat coronaviruses are of particular concern. To be better prepared for future pandemics, it is important to understand how many of these viruses exist and their ability to infect different hosts. However, research in this area has often focused on certain parts of the world, while other regions remain underexplored. Spain has a rich diversity of bats, but very few studies have looked for coronaviruses in bats from the Iberian Peninsula. Here, we used viral metagenomics to test for the presence of coronaviruses in more than 200 bat samples collected across Spain. We identified eight coronavirus genomes, three of which may constitute new species. We also examined how closely related they are to previously known viruses, and whether they can use the same cellular receptors as known coronaviruses. Notably, we found that one of the viruses could use human ACE2, the SARS-CoV-2 receptor. Our findings reveal that bats in Spain host a diverse range of coronaviruses, including some that could potentially infect humans. This highlights the importance of studying coronavirus diversity more broadly worldwide.

Source: PLoS Pathogens, https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1013371

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HKU5 #bat #merbecoviruses engage bat and #mink #ACE2 as entry #receptors

Abstract

Identifying receptors for bat coronaviruses is critical for spillover risk assessment, countermeasure development, and pandemic preparedness. While Middle East respiratory syndrome coronavirus (MERS-CoV) uses DPP4 for entry, the receptors of many MERS-related betacoronaviruses remain unknown. The bat merbecovirus HKU5 was previously shown to have an entry restriction in human cells. Using both pseudotyped and full-length virus, we show that HKU5 uses Pipistrellus abramus bat ACE2 but not human ACE2 or DPP4 as a receptor. Cryo-electron microscopy analysis of the virus-receptor complex and structure-guided mutagenesis reveal a spike and ACE2 interaction that is distinct from other ACE2-using coronaviruses. MERS-CoV vaccine sera poorly neutralize HKU5 informing pan-merbecovirus vaccine design. Notably, HKU5 can also engage American mink and stoat ACE2, revealing mustelids as potential intermediate hosts. These findings highlight the versatility of merbecovirus receptor use and underscore the need for continued surveillance of bat and mustelid species.

Source: Nature Communications, https://www.nature.com/articles/s41467-025-61583-7

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Genomic #Surveillance Detection of #SARS-CoV-1–Like Viruses in Rhinolophidae #Bats, Bandarban Region, #Bangladesh

Abstract

We sequenced sarbecovirus from Rhinolophus spp. bats in Bandarban District, Bangladesh, in a genomic surveillance campaign during 2022–2023. Sequences shared identity with SARS-CoV-1 Tor2, which caused an outbreak of human illnesses in 2003. Describing the genetic diversity and zoonotic potential of reservoir pathogens can aid in identifying sources of future spillovers.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/8/25-0071_article

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#Nipah Virus #Antibodies in #Bats, the #Philippines, 2013–2022

Abstract

In 2014, an outbreak of zoonotic Nipah virus (NiV) occurred on Mindanao Island, the Philippines. We investigated the prevalence of NiV in Philippine bats. Because neutralizing antibodies were detected in insectivorous bats on Siargao Island, public health officials should consider that the distribution range of NiV is not limited to Mindanao Island.

Source: US Centers for Disease Control and Prevention, https://wwwnc.cdc.gov/eid/article/31/8/25-0210_article

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Infectome analysis of #bat #kidneys from #Yunnan province, #China, reveals novel #henipaviruses related to #Hendra and #Nipah viruses and prevalent bacterial and eukaryotic microbes

Abstract

Bats are natural reservoirs for a wide range of microorganisms, including many notable zoonotic pathogens. However, the composition of the infectome (i.e., the collection of viral, bacterial and eukaryotic microorganisms) within bat kidneys remains poorly understood. To address this gap, we performed meta-transcriptomic sequencing on kidney tissues from 142 bats, spanning ten species sampled at five locations in Yunnan province, China. This analysis identified 22 viral species, including 20 novel viruses, two of which represented newly discovered henipaviruses closely related to the highly pathogenic Hendra and Nipah viruses. These henipaviruses were found in the kidneys of bats inhabiting an orchard near villages, raising concerns about potential fruit contamination via bat urine and transmission risks to livestock or humans. Additionally, we identified a novel protozoan parasite, tentatively named Klossiella yunnanensis, along with two highly abundant bacterial species, one of which is a newly discovered species—Flavobacterium yunnanensis. These findings broaden our understanding of the bat kidney infectome, underscore critical zoonotic threats, and highlight the need for comprehensive, full-spectrum microbial analyses of previously understudied organs to better assess spillover risks from bat populations.

Author summary

Although extensive investigations have been conducted on the bat virome, most studies have focused on fecal samples, leaving other tissues, such as the kidney, largely unexplored. However, the kidney can harbor important zoonotic pathogens, including the highly pathogenic Hendra and Nipah viruses, and genomic evidence of henipaviruses in bats from China has remained undocumented. In this study, we report the first detection of two novel henipavirus genomes from bat kidneys in China, one of which is the closest known relative of pathogenic henipaviruses identified to date. Beyond virome analysis, our study also examined highly prevalent bacteria and eukaryotic microbes, identifying those potentially relevant to bat infections. Overall, these findings provide valuable insights into the infectome of the bat kidney, highlighting the need for broader microbial surveillance beyond the gastrointestinal tract.

Source: PLoS Pathogens, https://journals.plos.org/plospathogens/article?id=10.1371/journal.ppat.1013235

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