-
Current Biology : CB Mar 2024Adaptive radiations are generated through a complex interplay of biotic and abiotic factors. Although adaptive radiations have been widely studied in the context of...
Adaptive radiations are generated through a complex interplay of biotic and abiotic factors. Although adaptive radiations have been widely studied in the context of animal and plant evolution, little is known about how they impact the evolution of the viruses that infect these hosts, which in turn may provide insights into the drivers of cross-species transmission and hence disease emergence. We examined how the rapid adaptive radiation of the cichlid fishes of African Lake Tanganyika over the last 10 million years has shaped the diversity and evolution of the viruses they carry. Through metatranscriptomic analysis of 2,242 RNA sequencing libraries, we identified 121 vertebrate-associated viruses among various tissue types that fell into 13 RNA and 4 DNA virus groups. Host-switching was commonplace, particularly within the Astroviridae, Metahepadnavirus, Nackednavirus, Picornaviridae, and Hepacivirus groups, occurring more frequently than in other fish communities. A time-calibrated phylogeny revealed that hepacivirus diversification was not constant throughout the cichlid radiation but accelerated 2-3 million years ago, coinciding with a period of rapid cichlid diversification and niche packing in Lake Tanganyika, thereby providing more closely related hosts for viral infection. These data depict a dynamic virus ecosystem within the cichlids of Lake Tanganyika, characterized by rapid virus diversification and frequent host jumping, and likely reflecting their close phylogenetic relationships that lower the barriers to cross-species virus transmission.
Topics: Animals; Phylogeny; Ecosystem; Tanzania; Lakes; Cichlids; Viruses
PubMed: 38428417
DOI: 10.1016/j.cub.2024.02.008 -
PLoS Pathogens Feb 2024Human astrovirus (HAstV) is a known cause of viral gastroenteritis in children worldwide, but HAstV can cause also severe and systemic infections in immunocompromised...
Human astrovirus (HAstV) is a known cause of viral gastroenteritis in children worldwide, but HAstV can cause also severe and systemic infections in immunocompromised patients. There are three clades of HAstV: classical, MLB, and VA/HMO. While all three clades are found in gastrointestinal samples, HAstV-VA/HMO is the main clade associated with meningitis and encephalitis in immunocompromised patients. To understand how the HAstV-VA/HMO can infect the central nervous system, we investigated its sequence-divergent capsid spike, which functions in cell attachment and may influence viral tropism. Here we report the high-resolution crystal structures of the HAstV-VA1 capsid spike from strains isolated from patients with gastrointestinal and neuronal disease. The HAstV-VA1 spike forms a dimer and shares a core beta-barrel structure with other astrovirus capsid spikes but is otherwise strikingly different, suggesting that HAstV-VA1 may utilize a different cell receptor, and an infection competition assay supports this hypothesis. Furthermore, by mapping the capsid protease cleavage site onto the structure, the maturation and assembly of the HAstV-VA1 capsid is revealed. Finally, comparison of gastrointestinal and neuronal HAstV-VA1 sequences, structures, and antigenicity suggests that neuronal HAstV-VA1 strains may have acquired immune escape mutations. Overall, our studies on the HAstV-VA1 capsid spike lay a foundation to further investigate the biology of HAstV-VA/HMO and to develop vaccines and therapeutics targeting it.
Topics: Child; Humans; Capsid; Mamastrovirus; Capsid Proteins; Mutation; Astroviridae Infections; Phylogeny; Feces
PubMed: 38416796
DOI: 10.1371/journal.ppat.1012028 -
Virology Journal Feb 2024Astroviruses (AstVs) are single-stranded RNA viruses that have been detected in a wide range of mammals and birds. They are associated with numerous interspecies...
BACKGROUND
Astroviruses (AstVs) are single-stranded RNA viruses that have been detected in a wide range of mammals and birds. They are associated with numerous interspecies transmissions and viral recombination events, posing a threat to human and animal health.
METHODS
We collected 1,333 samples from wild animals, including bats, rodents, wild boars, and birds, from various states and cities in the Yunnan Province, China, between 2020 and 2023 to investigate the presence of AstVs. AstVs were detected using a polymerase chain reaction targeting the RdRp gene. Finally, the Molecular Evolutionary Genetics Analysis software was used to construct the phylogenetic tree.
RESULTS
The overall positivity rate for AstVs was 7.12% in four species, indicating their widespread occurrence in the region. High genetic diversity among AstVs was observed in different animal species, suggesting the potential for interspecies transmission, particularly among rodents and birds. Additionally, we identified a novel AstV strain and, for the first time, provided information on the presence of bastroviruses in Yunnan, China.
CONCLUSIONS
The widespread distribution and high genetic diversity of AstVs, along with the observed potential for interspecies transmission, highlight the importance of further investigation and surveillance in the region. The findings emphasize the need for increased attention to AstVs and their potential impact on human and animal health in Yunnan and other regions.
Topics: Animals; Humans; Animals, Wild; Astroviridae Infections; Phylogeny; China; RNA Viruses; Mammals; Chiroptera; Rodentia
PubMed: 38414022
DOI: 10.1186/s12985-024-02314-0 -
Transplant Infectious Disease : An... Apr 2024We present a case of a 72-year-old liver transplant recipient 7 years prior who presents to our hospital with general malaise, fatigue, low-grade fevers, and watery...
We present a case of a 72-year-old liver transplant recipient 7 years prior who presents to our hospital with general malaise, fatigue, low-grade fevers, and watery diarrhea. He was found to have Astrovirus via PCR testing in a comprehensive stool panel. The patient's home mycophenolic acid was held upon admission, while cyclosporine was continued through his hospital stay. Generally, Astroviridae infection is a rarely identified cause of enteritis and even less so in the transplant population. Although reports have been published regarding devastating cases of encephalitis in immunocompromised patients, our patient did not exhibit these symptoms and draws into question the danger of this virus in other immunosuppressed populations. This case helps to better elucidate which patient populations should be approached with caution in the setting of Astroviridae infection.
Topics: Male; Humans; Aged; Astroviridae; Astroviridae Infections; Liver Transplantation; Diarrhea; Enteritis; Organ Transplantation
PubMed: 38407512
DOI: 10.1111/tid.14257 -
Journal of Medical Virology Mar 2024Human astrovirus (HAstV) is a nonenveloped RNA virus and has been implicated in acute gastroenteritis among children and elderly. However, there exists a substantial...
Human astrovirus (HAstV) is a nonenveloped RNA virus and has been implicated in acute gastroenteritis among children and elderly. However, there exists a substantial dearth of information on HAstV strains circulating in Nigeria. Viral-like particles were purified from archived 254 stool samples of children with acute flaccid paralysis between January and December 2020 from five states in Nigeria, using the NetoVIR protocol. Extracted viral RNA and DNA were subjected to a reverse transcription step and subsequent random polymerase chain reaction amplification. Library preparation and Illumina sequencing were performed. Using the virome paired-end reads pipeline, raw reads were processed into genomic contigs. Phylogenetic and pairwise identity analysis of the recovered HAstV genomes was performed. Six near-complete genome sequences of HAstV were identified and classified as HAstV4 (n = 1), HAstV5 (n = 1), HAstV8 (n = 1), and MLB-3 (n = 3). The HAstV5 belonged to a yet unclassified sublineage, which we tentatively named HAstV-5d. Phylogenetic analysis of open reading frames 1a, 1b, and 2 suggested recombination events inside the MAstV1 species. Furthermore, phylogenetic analysis implied a geographic linkage between the HAstV5 strain from this study with two strains from Cameroon across all the genomic regions. We report for the first time the circulation of HAstV genotypes 4, 8, and MLB-3 in Nigeria and present data suggestive for the existence of a new sublineage of HAstV5. To further understand the burden, diversity, and evolution of HAstV, increased research interest as well as robust HAstV surveillance in Nigeria is essential.
Topics: Child; Humans; Aged; Mamastrovirus; Phylogeny; Nigeria; Astroviridae Infections; Feces; Genotype
PubMed: 38402605
DOI: 10.1002/jmv.29489 -
Poultry Science Apr 2024Goose astrovirus (GAstV)-2, a novel pathogen identified in 2018, mainly causes visceral gout in goslings, leading to approximately 50% mortality. At present, no...
Goose astrovirus (GAstV)-2, a novel pathogen identified in 2018, mainly causes visceral gout in goslings, leading to approximately 50% mortality. At present, no commercial veterinary products are available to prevent and treat the disease. Our previous studies showed that nitric oxide (NO) and inducible NO synthase (iNOS) were markedly higher in the kidney and spleen of goslings infected with GAstV-2, but their effects during GAstV-2 infection remain unclear. In the present study, goslings were intraperitoneally injected with aminoguanidine (AG)-an iNOS inhibitor-to examine the role of NO during GAstV-2 infection. AG significantly decreased the serum NO concentration and iNOS mRNA expression in the kidney. Moreover, AG reduced the mortality, serum uric acid and creatinine content, and urate deposition in visceral organs and joints. Histopathological analysis demonstrated that AG reduced renal tubular cell necrosis, inflammatory cell infiltration, glycogen deposition in glomerular mesangium, and interstitial fibrosis, suggesting alleviation of kidney lesions. Furthermore, AG decreased the expression of renal injury markers such as KIM-1 and desmin; inflammatory cytokine-related genes such as IL-1β, IL-8, and MMP-9; and autophagy-related genes and proteins such as LC3II, ATG5, and Beclin1. However, quantitative real-time PCR and immunohistochemistry showed that treatment with AG did not affect the kidney and liver viral load. These findings suggest that AG decreases the mortality rate and kidney lesions in goslings infected with GAstV-2 through mechanisms associated with autophagy and inhibition of inflammatory cytokine production in the kidney but not with GAstV-2 replication.
Topics: Animals; Geese; Uric Acid; Chickens; Astroviridae; Gout; Astroviridae Infections; Kidney; Cytokines; Avastrovirus; Guanidines
PubMed: 38306918
DOI: 10.1016/j.psj.2024.103484 -
BMC Veterinary Research Jan 2024Enteric viruses are among the most prominent etiological agents of Runting-Stunting Syndrome (RSS). The Avian Nephritis Virus (ANV) is an astrovirus associated with...
Development of a fast and sensitive RT-qPCR assay based on SYBR® green for diagnostic and quantification of Avian Nephritis Virus (ANV) in chickens affected with enteric disease.
BACKGROUND
Enteric viruses are among the most prominent etiological agents of Runting-Stunting Syndrome (RSS). The Avian Nephritis Virus (ANV) is an astrovirus associated with enteric diseases in poultry, whose early diagnosis is essential for maintaining a good poultry breeding environment. ANV is an RNA virus that rapidly mutates, except for some conserved regions such as ORF1b. Therefore, the approach of a diagnostic method based on fast-RT-qPCR using SYBR® Green that focuses on the amplification of a fragment of ORF1b is presented as a feasible alternative for the diagnosis of this viral agent. In this study, the proposed assay showed a standard curve with an efficiency of 103.8% and a LoD and LoQ of 1 gene viral copies. The assay was specific to amplify the ORF 1b gene, and no amplification was shown from other viral genomes or in the negative controls. 200 enteric (feces) samples from chickens (broilers) and laying hens with signs of RSS from Ecuadorian poultry flocks were examined to validate the proposed method.
RESULTS
Using our method, 164 positive results were obtained out of the total number of samples run, while the presence of viral RNA was detected in samples collected from one day to 44 weeks old in both avian lines.
CONCLUSIONS
Our study presents a novel, rapid, robust, and sensitive molecular assay capable of detecting and quantifying even low copy numbers of the ANV in commercial birds, therefore introducing a handy tool in the early diagnosis of ANV in enteric disease outbreaks in poultry.
Topics: Animals; Female; Chickens; Avastrovirus; Astroviridae Infections; RNA, Viral; Poultry; RNA Viruses; Poultry Diseases
PubMed: 38291450
DOI: 10.1186/s12917-024-03881-8 -
Frontiers in Molecular Biosciences 2023Astroviruses are a family of genetically diverse viruses associated with disease in humans and birds with significant health effects and economic burdens. Astrovirus...
Astroviruses are a family of genetically diverse viruses associated with disease in humans and birds with significant health effects and economic burdens. Astrovirus taxonomic classification includes two genera, and However, with next-generation sequencing, broader interspecies transmission has been observed necessitating a reexamination of the current host-based taxonomic classification approach. In this study, a novel taxonomic classification method is presented for emergent and as yet unclassified astroviruses, based on whole genome sequence -mer composition in addition to host information. An optional component responsible for identifying recombinant sequences was added to the method's pipeline, to counteract the impact of genetic recombination on viral classification. The proposed three-pronged classification method consists of a supervised machine learning method, an unsupervised machine learning method, and the consideration of host species. Using this three-pronged approach, we propose genus labels for 191 as yet unclassified astrovirus genomes. Genus labels are also suggested for an additional eight as yet unclassified astrovirus genomes for which incompatibility was observed with the host species, suggesting cross-species infection. Lastly, our machine learning-based approach augmented by a principal component analysis (PCA) analysis provides evidence supporting the hypothesis of the existence of human astrovirus () subgenus of the genus , and a goose astrovirus () subgenus of the genus . Overall, this multipronged machine learning approach provides a fast, reliable, and scalable prediction method of taxonomic labels, able to keep pace with emerging viruses and the exponential increase in the output of modern genome sequencing technologies.
PubMed: 38274100
DOI: 10.3389/fmolb.2023.1305506 -
Viruses Jan 2024Astroviruses (AstVs) are small RNA viruses characterized by a high mutation rate, the ability to recombine, and interspecies transmission, which allows them to infect a...
Astroviruses (AstVs) are small RNA viruses characterized by a high mutation rate, the ability to recombine, and interspecies transmission, which allows them to infect a multitude of hosts including humans, companion animals, and farmed animals as well as wildlife. AstVs are stable in the environment, and their transmission is usually through the fecal-oral route or via contaminated water and food. Although direct zoonotic transmission was not confirmed, interspecies transmission events have occurred or have been indicated to occur in the past between wild and domestic animals and humans. They cause large economic losses, mainly in the poultry sector, due to gastroenteritis and mortality. In young children, they are the second most common cause of diarrhea. This study involved 166 intestine samples and pools of spleen, lymph node, and kidney samples collected from 352 wild animals, 52 pigs, and 31 companion animals. Astroviruses were detected in the intestine samples and were separately detected in pools of tissue samples prepared for individual animals using a heminested RT-PCR protocol. Amplicons were subjected to Sanger sequencing, and a phylogenetic analysis of 320 nt RNA-dependent RNA polymerase (RdRp) fragments referring to known nt sequences of astroviruses was performed. Astroviral RNA was detected in the intestine samples and/or tissue pools of red foxes (nine positive intestines and six positive tissue pools), rats (two positive intestines and three positive tissue pools), a cat (one AstV detected in an intestine sample), pigs (eight positive tissue pools), and wild boars (two positive pools of spleens, kidneys, and lymph nodes). No astroviral RNA was detected in wild mustelids, dogs, or other small wild animals including rodents. A phylogenetic analysis revealed that the astroviruses detected during this study were mostly host-specific, such as porcine, canine, and rat astroviruses that were highly homologous to the sequences of reference strains. In one of two wild boars, an AstV distinct to porcine species was found with the highest nt identity to , i.e., turkey astroviruses, which suggests potential cross-species transmission of the virus, as previously described. Here, we present the first detection of astroviruses in the population of wild animals, companion animals, and pigs in Poland, confirming that astroviruses are frequent pathogens circulating in animals in the field. Our study also suggests potential cross-species transmission of to wild boars; however, further molecular characterization is needed.
Topics: Humans; Child; Animals; Dogs; Cats; Rats; Swine; Child, Preschool; Poland; Prevalence; Phylogeny; RNA Viruses; Animals, Wild; Avastrovirus; Foxes; RNA; Sus scrofa
PubMed: 38257780
DOI: 10.3390/v16010080 -
Zhonghua Yu Fang Yi Xue Za Zhi [Chinese... Jan 2024To study the complete genome characterization of Human Astrovirus (HAstV) in Shandong Province. Stool samples from acute flaccid paralysis (AFP) surveillance in...
To study the complete genome characterization of Human Astrovirus (HAstV) in Shandong Province. Stool samples from acute flaccid paralysis (AFP) surveillance in Shandong Province from 2020 to 2022 were collected, and HAstV nucleic acid was examined by real-time quantitative PCR (qPCR). Next-generation sequencing (NGS) was conducted for the positive samples to obtain complete genome sequences and identify the genotype. Homology comparison and phylogenetic analysis were performed by using BioEdit and Mega software. A total of 667 samples were examined by qPCR, of which 14 were HAstV-positive (2.1%), including HAstV-1 (=6), MLB1 (=6), MLB2 (=1), and VA2 (=1). The complete genome sequences were obtained from 11 samples. The six HAstV-1 sequences of this study had 98.2% to 99.9% nt similarities with each other and 87.6% to 98.6% with those from other regions. The four MLB1 sequences of this study had 99.1% to 99.9% nt similarities with each other and 92.2% to 99.4% with those from other regions. The VA2 sequence of this study had 96.0% to 96.3% nt similarities with those from other regions. Phylogenetic analysis based on ORF2 region showed that the local HAstV-1 sequences were most closely related to Japanese strains, and had distinct topology with phylogenies based on ORF1a and ORF1b regions. The complete genome sequences of 11 HAstV strains are obtained, and the VA2 complete genome is found.
Topics: Humans; Mamastrovirus; Phylogeny; Astroviridae Infections; Feces; Sequence Analysis, DNA; Genotype; Real-Time Polymerase Chain Reaction
PubMed: 38228548
DOI: 10.3760/cma.j.cn112150-20230509-00357