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Avian Pathology : Journal of the W.V.P.A Oct 2022Five novel chicken astrovirus (CAstV) strains, designated ZDF, MHC, WSC, WSW and MHW, were successfully isolated from chickens with gout, and were subjected to full...
Five novel chicken astrovirus (CAstV) strains, designated ZDF, MHC, WSC, WSW and MHW, were successfully isolated from chickens with gout, and were subjected to full genome sequencing characterization and tested for their pathogenic effects in specific pathogen-free (SPF) chicken embryos and chickens. The complete genomes of the five isolated strains were approximately 7436 nt to 7511 nt in length. Phylogenetic analysis revealed that strains ZDF and MHC were clustered in a clade with strains isolated in China and that the others were clustered with strains from other countries. Based on the amino acids of ORF2, strains MHW and WSW belonged to subgroup Ai, strain WSC belonged to Bii, and strains ZDF and MHC belonged to Bi. The pathogenicity of strains MHW, MHC and WSC, all belonging to different subgroups was studied. The results showed that the mortality of the chicken embryos was 100% when infected with any strain at a dose of more than 10 TCID, 35% in SPF chickens infected with strain WSC, 25% with MHC and 15% with MHW. The body weights of chickens and embryos infected with 0.2 ml 10 TCID were significantly reduced after hatching. SPF chickens infected with any of the strains had similar lesions characterized by urate deposits on the epicardium and kidney, and necrotic spots on the liver. This study identified the three types of genotypic CAstV prevalent in China, with high mortality in embryonated chicken eggs and leading to white chick syndrome, retarded growth and visceral gout in infected chicks.
Topics: Animals; Astroviridae Infections; Avastrovirus; Chick Embryo; Chickens; China; Genetic Variation; Gout; Phylogeny; Poultry Diseases; Virulence
PubMed: 35838631
DOI: 10.1080/03079457.2022.2102966 -
Journal of Virology Sep 2023Human astrovirus is a positive-sense, single-stranded RNA virus. Astrovirus infection causes gastrointestinal symptoms and can lead to encephalitis in immunocompromised...
Human astrovirus is a positive-sense, single-stranded RNA virus. Astrovirus infection causes gastrointestinal symptoms and can lead to encephalitis in immunocompromised patients. Positive-strand RNA viruses typically utilize host intracellular membranes to form replication organelles, which are potential antiviral targets. Many of these replication organelles are double-membrane vesicles (DMVs). Here, we show that astrovirus infection leads to an increase in DMV formation through a replication-dependent mechanism that requires some early components of the autophagy machinery. Results indicate that the upstream class III phosphatidylinositol 3-kinase (PI3K) complex, but not LC3 conjugation machinery, is utilized in DMV formation. Both chemical and genetic inhibition of the PI3K complex lead to significant reduction in DMVs, as well as viral replication. Elucidating the role of autophagy machinery in DMV formation during astrovirus infection reveals a potential target for therapeutic intervention for immunocompromised patients. IMPORTANCE These studies provide critical new evidence that astrovirus replication requires formation of double-membrane vesicles, which utilize class III phosphatidylinositol 3-kinase (PI3K), but not LC3 conjugation autophagy machinery, for biogenesis. These results are consistent with replication mechanisms for other positive-sense RNA viruses suggesting that targeting PI3K could be a promising therapeutic option for not only astrovirus, but other positive-sense RNA virus infections.
Topics: Humans; Autophagy; Class III Phosphatidylinositol 3-Kinases; Intracellular Membranes; Organelles; Phosphatidylinositol 3-Kinase; RNA Viruses; Virus Replication; Mamastrovirus; Signal Transduction
PubMed: 37668367
DOI: 10.1128/jvi.01025-23 -
Viruses Feb 2017Bats belong to the order Chiroptera that represents the second largest order of mammals with more than 1200 species and an almost global distribution. Environmental... (Review)
Review
Bats belong to the order Chiroptera that represents the second largest order of mammals with more than 1200 species and an almost global distribution. Environmental changes and deforestation have severely influenced many ecosystems, intensifying the contact between wildlife and humans. In recent years, bats have been found to harbor a number of different viruses with zoonotic potential, as well as a great diversity of astroviruses, for which the question of zoonotic potential remains unanswered to date. Human astroviruses have been identified as the causative agent for diarrhea in children and immunocompromised patients. For a long time, astroviruses have been considered to be strictly species-specific. However, a great genetic diversity has recently been discovered among animal and human astroviruses that might indicate the potential of these viruses to cross species barriers. Furthermore, our knowledge about the tissue tropism of astroviruses has been expanded to some neurotropic strains that have recently been shown to be responsible for encephalitis in humans and livestock. This review gives an overview on what is known about astroviruses in bats, humans and livestock, especially bovines and pigs. Future research activities are suggested to unravel astrovirus infection dynamics in bat populations to further assess the zoonotic potential of these viruses.
Topics: Animals; Astroviridae Infections; Chiroptera; Humans; Livestock; Mamastrovirus
PubMed: 28230787
DOI: 10.3390/v9020034 -
Research in Veterinary Science Aug 2023Astroviruses have been identified in a wide variety of animal species and are associated with gastro-intestinal disease in humans. Pathologies due to extra-intestinal...
Astroviruses have been identified in a wide variety of animal species and are associated with gastro-intestinal disease in humans. Pathologies due to extra-intestinal localization are known in different hosts. We report the detection of astroviruses in synanthropic squamate reptile species (Podercis siculus and Tarentola mauritanica). Fecal samples were collected from 100 squamates from urban and peri-urban areas of three regions in South Italy and tested for the presence of astroviruses using a broadly reactive (pan-astrovirus) RT-PCR protocol targeting the RNA-dependent RNA polymerase. Astrovirus RNA was detected in 11% of the samples and for six strains a 3 kb-long fragment at the 3' end of the genome was sequenced, obtaining information on the complete capsid-encoding ORF2 sequence. Viral RNA was also detected in the brain of one of the positive animals. The sequences generated from the astrovirus strains shared low nucleotide identities in the ORF2 (< 43.7%) with other known reptilian astrovirus sequences, hinting to the massive genetic diversity of members of this viral family. Based on the partial RdRp gene of the sequenced strains, however, we observed species-specific patterns, regardless of the geographic origin of the animals, and we also identified a possible inter-species transmission event between geckoes and lizards.
Topics: Humans; Animals; Astroviridae Infections; Astroviridae; RNA Viruses; RNA, Viral; Genome, Viral; Phylogeny
PubMed: 37331242
DOI: 10.1016/j.rvsc.2023.06.009 -
Infection, Genetics and Evolution :... Sep 2021Rodents including rats are reservoir of several pathogens capable of affecting human health. In this study, faecal and different organ specimens from free-living Norway...
Genome characterization, prevalence and tissue distribution of astrovirus, hepevirus and norovirus among wild and laboratory rats (Rattus norvegicus) and mice (Mus musculus) in Hungary.
Rodents including rats are reservoir of several pathogens capable of affecting human health. In this study, faecal and different organ specimens from free-living Norway rats (Rattus norvegicus) (N = 18) and faecal samples from laboratory rodents (rats N = 21 and mice N = 20) collected from different geographic areas in Hungary between 2017 and 2020 were investigated by viral metagenomics and conventional RT-PCR methods. The complete genome of three different RNA viruses, rat astrovirus, rat norovirus and rat hepevirus were characterized and analysed in detail. Rat norovirus was detected in faecal (17.6%, 3/17) and kidney (7.1%, 1/14) samples; rat astrovirus in faecal (23.5%, 4/17) and spleen (13.3%, 2/15) samples, and rat hepevirus in 43% to 67% the faecal, liver, kidney, lung, heart, muscle, brain and blood samples from Norway rats, respectively. Rat norovirus was also identifiable in 5% (1/21) of laboratory rats and rat astrovirus in 40% (8/20) of faecal samples from laboratory mice. Co-infections were found in 28% (5/18) wild Norway rats. The highest RNA viral load of astrovirus (1.81 × 10 copy/g) and norovirus (3.49 × 10 copy/g) were measured in faecal samples; while the highest RNA viral load of hepevirus (1.16 × 10 copy/g) was found in liver samples of Norway rats, respectively. This study confirms the wide geographic distribution and high prevalence of astrovirus, norovirus and hepevirus among wild rats in Hungary with confirmation of different organ involvement of as well as the detection of norovirus and astrovirus in laboratory rats and mice, respectively. This finding further strengthens the role of rodents in the spread of viral pathogens especially infecting human.
Topics: Animals; Animals, Laboratory; Animals, Wild; Astroviridae; Astroviridae Infections; Caliciviridae Infections; Hepatitis, Viral, Animal; Hepevirus; Hungary; Mice; Norovirus; RNA Virus Infections; Rats
PubMed: 34044191
DOI: 10.1016/j.meegid.2021.104942 -
Advances in Virus Research 2017Astroviruses are best known as being one of the leading causes of diarrhea in infants and were first described in this context in 1975. In its first years, astrovirus... (Review)
Review
Astroviruses are best known as being one of the leading causes of diarrhea in infants and were first described in this context in 1975. In its first years, astrovirus research was mainly restricted to electron microscopy and serology studies. The ability to culture some of these viruses in vitro allowed a first consequent step forward, especially at the molecular level. Since the emergence of more powerful genetic methods, though, the face of this research field has dramatically changed and evolved. From the exponential number of discoveries of new astrovirus strains in the most varied of animal species to their association with atypical diseases, these viruses revealed a lot of surprises, and many more are probably still waiting to be uncovered. This chapter summarizes the most important knowledge about astroviruses and discusses the implication of the latest findings in this area of research.
Topics: Animals; Astroviridae Infections; Humans; Mamastrovirus
PubMed: 29029723
DOI: 10.1016/bs.aivir.2017.07.002 -
Infection, Genetics and Evolution :... Mar 2018Environmental modifications are leading to biodiversity changes, loss and habitat disturbance. This in turn increases contacts between wildlife and hence the risk of...
Environmental modifications are leading to biodiversity changes, loss and habitat disturbance. This in turn increases contacts between wildlife and hence the risk of transmission and emergence of zoonotic diseases. We analyzed the environment and land use using remote spatial data around the sampling locations of bats positive for coronavirus (21 sites) and astrovirus (11 sites) collected in 43 sites. A clear association between viruses and hosts was observed. Viruses associated to synanthropic bat genera, such as Myotis or Scotophilus were associated to highly transformed habitats with human presence while viruses associated to fruit bat genera were correlated with natural environments with dense forest, grassland areas and regions of high elevation. In particular, group C betacoronavirus were associated with mosaic habitats found in anthropized environments.
Topics: Animals; Astroviridae; Cambodia; Chiroptera; Cluster Analysis; Coronavirus; Environmental Microbiology; Genetic Variation; Humans; Laos; Mice; Phylogeny; Phylogeography; RNA Viruses; Zoonoses
PubMed: 29277555
DOI: 10.1016/j.meegid.2017.12.009 -
Viruses Oct 2022Astroviruses (AstVs) are single-stranded RNA viruses, including two main genera: Mamastroviruses (MAstVs) and Avastroviruses (AAstVs). AstVs have been detected in more...
Astroviruses (AstVs) are single-stranded RNA viruses, including two main genera: Mamastroviruses (MAstVs) and Avastroviruses (AAstVs). AstVs have been detected in more than 80 different mammals and birds, with the characteristics of multiple cross-species transmission and gene recombination. All these have accelerated the process of virus mutation and posed a potential threat to human beings and animal husbandry. Yunnan province is a global hotspot with rich biodiversity and abundant animal resources and an important area with significance for public health and security because it neighbors a few Southeast Asian countries. This study collected 860 samples from 13 species of animals in Yunnan province for AstVs detection. The results showed that the positive rate of AstVs was 6.05%, and its extremely high genetic diversity was observed in different animal species. Potential cross-species transmission events were also detected from rodents to birds. Therefore, AstVs, which are widely distributed with highly diverse genes and the risk of cross-species transmission to people, deserve more attention in this region.
Topics: Animals; Humans; Astroviridae Infections; Phylogeny; China; Avastrovirus; Mamastrovirus; Mammals; Birds; Rodentia; Genetic Variation
PubMed: 36298789
DOI: 10.3390/v14102234 -
Letters in Applied Microbiology Mar 2015Cross-priming amplification (CPA) was evaluated for the early detection of norovirus (NV), rotavirus A (RV-A), enteric adenovirus (EAdV) and astrovirus (AstV). The...
UNLABELLED
Cross-priming amplification (CPA) was evaluated for the early detection of norovirus (NV), rotavirus A (RV-A), enteric adenovirus (EAdV) and astrovirus (AstV). The analytical sensitivity of the CPA assay was 10(3) copies ml(-1) for NV, RV-A and AstV detection and 10(4) copies ml(-1) for EAdV detection. For each of the four pathogens, the positive detection rate by CPA was similar to real-time PCR methods and higher than the rate observed in an ELISA. The detection coincidence rates of CPA and RT-PCR for NV, RV-A, EAdV and AstV were 98, 99, 99 and 100%, respectively. All CPA assays were negative in 89 healthy control samples. These results demonstrate the high analytical sensitivity and specificity of the CPA assay. CPA assays are relatively straightforward to perform, and such assays represent a potential detection method for locations in which resources are limited.
SIGNIFICANCE AND IMPACT OF THE STUDY
Over one billion people suffer from diarrhoeal diseases every year. This leads to significant morbidity and mortality, particularly the children under five. Rapid and specific detection of the pathogens that cause diarrhoeal diseases would be advantageous, enabling rapid treatment and management of the spread of pathogens. Here, a fast, cross-contamination-proof and user-friendly nucleic acid isothermal amplification method called cross-priming amplification (CPA) was used to test four pathogens with high analytical sensitivity and specificity. The results indicate that CPA has great potential for improving medical diagnostics, particularly in resource-limited areas.
Topics: Adenoviridae; Adenoviridae Infections; Astroviridae Infections; Caliciviridae Infections; Child; Diarrhea; Enzyme-Linked Immunosorbent Assay; Humans; Mamastrovirus; Norovirus; Nucleic Acid Amplification Techniques; Retrospective Studies; Rotavirus; Rotavirus Infections; Sensitivity and Specificity
PubMed: 25346035
DOI: 10.1111/lam.12342 -
Viruses Dec 2021White chick hatchery disease is an emerging disease of broiler chicks with which the virus, chicken astrovirus, has been associated. Adult birds typically show no... (Review)
Review
White chick hatchery disease is an emerging disease of broiler chicks with which the virus, chicken astrovirus, has been associated. Adult birds typically show no obvious clinical signs of infection, although some broiler breeder flocks have experienced slight egg drops. Substantial decreases in hatching are experienced over a two-week period, with an increase in mid-to-late embryo deaths, chicks too weak to hatch and pale, runted chicks with high mortality. Chicken astrovirus is an enteric virus, and strains are typically transmitted horizontally within flocks via the faecal-oral route; however, dead-in-shell embryos and weak, pale hatchlings indicate vertical transmission of the strains associated with white chick hatchery disease. Hatch levels are typically restored after two weeks when seroconversion of the hens to chicken astrovirus has occurred. Currently, there are no commercial vaccines available for the virus; therefore, the only means of protection is by good levels of biosecurity. This review aims to outline the current understanding regarding white chick hatchery disease in broiler chick flocks suffering from severe early mortality and increased embryo death in countries worldwide.
Topics: Animal Husbandry; Animals; Astroviridae Infections; Avastrovirus; Chickens; Communicable Diseases, Emerging; Disease Progression; Poultry Diseases
PubMed: 34960704
DOI: 10.3390/v13122435