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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 -
Viruses Apr 2021Astroviruses are single stranded, positive-sense RNA viruses that have been historically associated with diseases of the gastrointestinal tract of vertebrates, including... (Review)
Review
Astroviruses are single stranded, positive-sense RNA viruses that have been historically associated with diseases of the gastrointestinal tract of vertebrates, including humans. However, there is now a multitude of evidence demonstrating the capacity of these viruses to cause extraintestinal diseases. The most striking causal relationship is neurological diseases in humans, cattle, pigs, and other mammals, caused by astrovirus infection. Astroviruses have also been associated with disseminated infections, localized disease of the liver or kidneys, and there is increasing evidence suggesting a potential tropism to the respiratory tract. This review will discuss the current understanding of the tissue tropisms for astroviruses and their emerging capacity to cause disease in multiple organ systems.
Topics: Animals; Astroviridae; Astroviridae Infections; Disease Susceptibility; Gastroenteritis; Genetic Variation; Genome, Viral; Humans; Organ Specificity; RNA, Viral; Viral Tropism
PubMed: 33922259
DOI: 10.3390/v13050732 -
Veterinary Research Dec 2023It is well-established that the genetic diversity, regional prevalence, and broad host range of astroviruses significantly impact the poultry industry. In July 2022, a...
It is well-established that the genetic diversity, regional prevalence, and broad host range of astroviruses significantly impact the poultry industry. In July 2022, a small-scale commercial broiler farm in China reported cases of growth retardation and a 3% mortality rate. From chickens displaying proventriculitis and pancreatitis, three chicken astroviruses (CAstV) isolates were obtained and named SDAU2022-1-3. Complete genomic sequencing and analysis revealed the unique characteristics of these isolates from known CAstV strains in ORF1a, ORF1b, and ORF2 genes, characterized by an unusually high variability. Analysis of amino acid mutations in ORF1a, ORF1b, and ORF2 indicated that the accumulation of these mutations played a pivotal role in the emergence of the variant strain. Inoculation experiments demonstrated that affected chickens exhibited liver and kidney enlargement, localized proventricular hemorrhage, and a dark reddish-brown appearance in about two-thirds of the pancreas. Histopathological examination unveiled hepatic lymphocytic infiltration, renal tubular epithelial cell swelling, along with lymphocytic proventriculitis and pancreatitis. Quantitative reverse transcription-polymerase chain reaction (qRT-PCR) analysis indicated viremia and viral shedding at 3 days post-infection (dpi). The proventriculus displayed the highest viral loads, followed by the liver, kidney, duodenum, and pancreas. Liver parameters (AST and ALT) and kidney parameters (UA and UN) demonstrated mild damage consistent with earlier findings. While the possibility of new mutations in the ORF2 gene of CAstV causing proventriculitis and pancreatitis warrants further investigation, these findings deepen our comprehension of CAstV's pathogenicity in chickens. Additionally, they serve as valuable references for subsequent research endeavors.
Topics: Animals; Avastrovirus; Chickens; Virulence; Astroviridae Infections; Pancreatitis; Poultry Diseases; Phylogeny
PubMed: 38066626
DOI: 10.1186/s13567-023-01250-1 -
Viruses Feb 2021Since the 1970s, eight closely related serotypes of classical human astroviruses (HAstV) have been associated with gastrointestinal illness worldwide. In the late 2000s,...
Since the 1970s, eight closely related serotypes of classical human astroviruses (HAstV) have been associated with gastrointestinal illness worldwide. In the late 2000s, three genetically unique human astrovirus clades, VA1-VA3, VA2-VA4, and MLB, were described. While the exact disease associated with these clades remains to be defined, VA1 has been associated with central nervous system infections. The discovery that VA1 could be grown in cell culture, supports exciting new studies aimed at understanding viral pathogenesis. Given the association of VA1 with often lethal CNS infections, we tested its susceptibility to the antimicrobial drug, nitazoxanide (NTZ), which we showed could inhibit classical HAstV infections. Our studies demonstrate that NTZ inhibited VA1 replication in Caco2 cells even when added at 12 h post-infection, which is later than in HAstV-1 infection. These data led us to further probe VA1 replication kinetics and cellular responses to infection in Caco-2 cells in comparison to the well-studied HAstV-1 strain. Overall, our studies highlight that VA1 replicates more slowly than HAstV-1 and elicits significantly different cellular responses, including the inability to disrupt cellular junctions and barrier permeability.
Topics: Anti-Infective Agents; Astroviridae; Astroviridae Infections; Caco-2 Cells; Cell Line, Tumor; Central Nervous System; Humans; Nitro Compounds; Phylogeny; RNA, Viral; Thiazoles; Virus Replication
PubMed: 33673521
DOI: 10.3390/v13030376 -
Journal of Infection and Public Health Aug 2023Human astrovirus (HAstV) infection is one of the leading causes of acute gastroenteritis in young children. The present study reports the outbreak of HAstV in children...
BACKGROUND
Human astrovirus (HAstV) infection is one of the leading causes of acute gastroenteritis in young children. The present study reports the outbreak of HAstV in children with acute gastroenteritis in Kyoto, Japan, during the COVID-19 pandemic, 2021.
METHODS
A total of 61 stool samples were collected from children with acute gastroenteritis who visited a pediatric outpatient clinic in Maizuru city, Kyoto, Japan from July to October, 2021. HAstV was screened by RT-PCR, and the genotypes were identified by nucleotide sequence analysis.
RESULTS
Of 61 cases of acute gastroenteritis, 20 were mono-infected with HAstV alone. In addition, mixed infection of HAstV and NoV, and HAstV and RVA were also detected in 15 and 1 cases, respectively. Of 36 HAstV strains detected in this outbreak, 29 and 7 were HAstV1 and MLB2 genotypes, respectively. All HAstV1 strains were closely related to the HAstV1 reported from Thailand and Japan in 2021 and all of them belonged to subgenotype HAstV1a. Among MLB2, they were most closely related to the MLB2 strains reported from China in 2016 and 2018.
CONCLUSIONS
After the kindergartens and schools were re-opened at the middle of 2021 in Japan, an outbreak of HAstV was reported. Control measures against the COVID-19 pandemics might affect the spread of diarrheal virus infection. Here we report the outbreak of HAstV1 and MLB2 in Kyoto, Japan, during COVID-19 pandemic in 2021.
Topics: Child; Humans; Infant; Child, Preschool; Mamastrovirus; Japan; Pandemics; COVID-19; Phylogeny; Feces; Gastroenteritis; Astroviridae Infections; Genotype
PubMed: 37336127
DOI: 10.1016/j.jiph.2023.05.034 -
The Journal of Hygiene Dec 1982Two serotypes of human astroviruses are described. It is proposed that these should be called serotype 1 and serotype 2. Using antisera to these two types, 13 of 15...
Two serotypes of human astroviruses are described. It is proposed that these should be called serotype 1 and serotype 2. Using antisera to these two types, 13 of 15 other community-acquired strains were able to be typed, 12 as serotype 1 and one as serotype 2.
Topics: Antigens, Viral; Humans; Mamastrovirus; Serotyping; Viruses, Unclassified
PubMed: 6818278
DOI: 10.1017/s0022172400071114 -
Poultry Science Aug 2023Goose astrovirus genotype 2 (GAstV-2) is the causative agent causing severe visceral gout and joint gout in goslings, with mortality rates of affected flocks up to 50%....
Goose astrovirus genotype 2 (GAstV-2) is the causative agent causing severe visceral gout and joint gout in goslings, with mortality rates of affected flocks up to 50%. To date, continuous GAstV-2 outbreaks still pose a great threat to goose industry in China. Although most researches on GAstV-2 have focused on its pathogenicity to geese and ducks, limited studies have been performed on chickens. Herein, we inoculated 1-day-old specific pathogen-free (SPF) White Leghorn line chickens with 0.6 mL of GAstV-2 culture supernatant (TCID 10/0.1 mL) via orally, subcutaneously and intramuscularly, and then assessed the pathogenicity. The results revealed that the infected chickens presented depression, anorexia, diarrhea, and weight loss. The infected chickens also suffered from extensive organ damage and had histopathological changes in the heart, liver, spleen, kidney, and thymuses. The infected chickens also had high viral load in tissues and shed virus after the challenge. Overall, our research demonstrates that GAstV-2 can infect chickens and adversely affect the productivity of animals. And the viruses shed by infected chickens can pose a potential risk to the same or other domestic landfowls.
Topics: Animals; Geese; Chickens; Astroviridae Infections; Virulence; Poultry Diseases; Avastrovirus; Gout; Genotype; China; Phylogeny
PubMed: 37302333
DOI: 10.1016/j.psj.2023.102808 -
Microbiology Spectrum Jun 2023Human astroviruses (HAstVs) are important causative pathogens of acute gastroenteritis (AGE) in children worldwide. MLB and VA HAstVs, which are genetically distinct...
Human astroviruses (HAstVs) are important causative pathogens of acute gastroenteritis (AGE) in children worldwide. MLB and VA HAstVs, which are genetically distinct from the previously known classic HAstVs, have been detected since 2008. To investigate the role of HAstVs in AGE, we conducted molecular detection and characterization of HAstVs circulating in children with AGE in Japan from 2014 to 2021. Out of 2,841 stool samples, HAstVs were detected in 130 (4.6%). MLB1 was the predominant genotype detected (45.4%), followed by HAstV1 (39.2%), MLB2 (7.4%), VA2 (3.1%), HAstV3 (2.3%), HAstV4, HAstV5, and MLB3 (0.8% each). The results demonstrated that HAstV infection in pediatric patients in Japan was dominated by the two major genotypes MLB1 and HAstV1, with a small proportion of other genotypes. The overall infection rates of MLB and VA HAstVs were higher than those of classic HAstVs. The HAstV1 strains detected in this study belonged solely to lineage 1a. The rare MLB3 genotype was detected for the first time in Japan. All three HAstV3 strains belonged to lineage 3c based on the ORF2 nucleotide sequence and were shown to be recombinant strains. HAstVs are one of the pathogens of viral AGE and are considered the third most common viral agents of AGE after rotavirus and norovirus. HAstVs are also suspected to be the causative agents of encephalitis or meningitis in immunocompromised patients and elderly persons. However, little is known about the epidemiology of HAstVs in Japan, especially that of MLBs and VA HAstVs. This study demonstrated epidemiological features and molecular characterization of human astroviruses encompassing a 7-year study period in Japan. This study highlights the genetic diversity of HAstV circulating in pediatric patients with acute AGE in Japan.
Topics: Humans; Child; Aged; Molecular Epidemiology; Japan; Astroviridae Infections; Feces; Phylogeny; Gastroenteritis; Mamastrovirus
PubMed: 37140393
DOI: 10.1128/spectrum.00700-23 -
Uirusu Dec 2000
Review
Topics: Amino Acid Sequence; Animals; Astroviridae Infections; Capsid; Capsid Proteins; Genome, Viral; Glycoproteins; Humans; Mamastrovirus; Molecular Sequence Data; Prevalence; Proteins; Serotyping
PubMed: 11276809
DOI: No ID Found -
Nature Communications Aug 2020Human astroviruses are small non-enveloped viruses with positive-sense single-stranded RNA genomes. Astroviruses cause acute gastroenteritis in children worldwide and...
Human astroviruses are small non-enveloped viruses with positive-sense single-stranded RNA genomes. Astroviruses cause acute gastroenteritis in children worldwide and have been associated with encephalitis and meningitis in immunocompromised individuals. It is still unknown how astrovirus particles exit infected cells following replication. Through comparative genomic analysis and ribosome profiling we here identify and confirm the expression of a conserved alternative-frame ORF, encoding the protein XP. XP-knockout astroviruses are attenuated and pseudo-revert on passaging. Further investigation into the function of XP revealed plasma and trans Golgi network membrane-associated roles in virus assembly and/or release through a viroporin-like activity. XP-knockout replicons have only a minor replication defect, demonstrating the role of XP at late stages of infection. The discovery of XP advances our knowledge of these important human viruses and opens an additional direction of research into their life cycle and pathogenesis.
Topics: Animals; Cell Line; Cricetinae; Electrophoresis, Polyacrylamide Gel; Genomics; HeLa Cells; Humans; Immunoblotting; Immunoprecipitation; Ion Channels; Mamastrovirus; Microscopy, Fluorescence; Plasmids; Ribosomes; Viral Nonstructural Proteins; Viroporin Proteins; Virus Replication
PubMed: 32792502
DOI: 10.1038/s41467-020-17906-x