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1
Desselberger, Ulrich. « Caliciviridae Other Than Noroviruses ». Viruses 11, no 3 (21 mars 2019) : 286. http://dx.doi.org/10.3390/v11030286.
Texte intégralRésumé :
Besides noroviruses, the Caliciviridae family comprises four other accepted genera: Sapovirus, Lagovirus, Vesivirus, and Nebovirus. There are six new genera proposed: Recovirus, Valovirus, Bavovirus, Nacovirus, Minovirus, and Salovirus. All Caliciviridae have closely related genome structures, but are genetically and antigenically highly diverse and infect a wide range of mammalian host species including humans. Recombination in nature is not infrequent for most of the Caliciviridae, contributing to their diversity. Sapovirus infections cause diarrhoea in pigs, humans and other mammalian hosts. Lagovirus infections cause systemic haemorrhagic disease in rabbits and hares, and vesivirus infections lead to lung disease in cats, vesicular disease in swine, and exanthema and diseases of the reproductive system in large sea mammals. Neboviruses are an enteric pathogen of cattle, differing from bovine norovirus. At present, only a few selected caliciviruses can be propagated in cell culture (permanent cell lines or enteroids), and for most of the cultivatable caliciviruses helper virus-free, plasmid only-based reverse genetics systems have been established. The replication cycles of the caliciviruses are similar as far as they have been explored: viruses interact with a multitude of cell surface attachment factors (glycans) and co-receptors (proteins) for adsorption and penetration, use cellular membranes for the formation of replication complexes and have developed mechanisms to circumvent innate immune responses. Vaccines have been developed against lagoviruses and vesiviruses, and are under development against human noroviruses.
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Delwart, Eric, Michael J. Tisza, Eda Altan, Yanpeng Li, Xutao Deng, Dennis J. Hartigan-O’Connor et Amir Ardeshir. « Idiopathic Chronic Diarrhea in Rhesus Macaques Is Not Associated with Enteric Viral Infections ». Viruses 13, no 12 (14 décembre 2021) : 2503. http://dx.doi.org/10.3390/v13122503.
Texte intégralRésumé :
While recent changes in treatment have reduced the lethality of idiopathic chronic diarrhea (ICD), this condition remains one of the most common causes of rhesus macaque deaths in non-human primate research centers. We compared the viromes in fecal swabs from 52 animals with late stage ICD and 41 healthy animals. Viral metagenomics targeting virus-like particles was used to identify viruses fecally shed by each animal. Five viruses belonging to the Picornaviridae, one to the Caliciviridae, one to the Parvoviridae, and one to the Adenoviridae families were identified. The fraction of reads matching each viral species was then used to estimate and compare viral loads in ICD cases versus healthy controls. None of the viruses detected in fecal swabs were strongly associated with ICD.
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Fernandez-Cassi, Xavier, Sandra Martínez-Puchol, Marcelle Silva-Sales, Thais Cornejo, Rosa Bartolome, Silvia Bofill-Mas et Rosina Girones. « Unveiling Viruses Associated with Gastroenteritis Using a Metagenomics Approach ». Viruses 12, no 12 (13 décembre 2020) : 1432. http://dx.doi.org/10.3390/v12121432.
Texte intégralRésumé :
Acute infectious gastroenteritis is an important illness worldwide, especially on children, with viruses accounting for approximately 70% of the acute cases. A high number of these cases have an unknown etiological agent and the rise of next generation sequencing technologies has opened new opportunities for viral pathogen detection and discovery. Viral metagenomics in routine clinical settings has the potential to identify unexpected or novel variants of viral pathogens that cause gastroenteritis. In this study, 124 samples from acute gastroenteritis patients from 2012–2014 previously tested negative for common gastroenteritis pathogens were pooled by age and analyzed by next generation sequencing (NGS) to elucidate unidentified viral infections. The most abundant sequences detected potentially associated to acute gastroenteritis were from Astroviridae and Caliciviridae families, with the detection of norovirus GIV and sapoviruses. Lower number of contigs associated to rotaviruses were detected. As expected, other viruses that may be associated to gastroenteritis but also produce persistent infections in the gut were identified including several Picornaviridae members (EV, parechoviruses, cardioviruses) and adenoviruses. According to the sequencing data, astroviruses, sapoviruses and NoV GIV should be added to the list of viral pathogens screened in routine clinical analysis.
4
Barry, Aline F., Alice F. Alfieri et Amauri A. Alfieri. « Detection and phylogenetic analysis of porcine enteric calicivirus, genetically related to the Cowden strain of sapovirus genogroup III, in Brazilian swine herds ». Pesquisa Veterinária Brasileira 28, no 1 (janvier 2008) : 82–86. http://dx.doi.org/10.1590/s0100-736x2008000100013.
Texte intégralRésumé :
Sapovirus of the Caliciviridae family is an important agent of acute gastroenteritis in children and piglets. The Sapovirus genus is divided into seven genogroups (G), and strains from the GIII, GVI and GVII are associated with infections in swine. Despite the high prevalence in some countries, there are no studies related to the presence of porcine enteric sapovirus infections in piglets in Brazil. In the present study, 18 fecal specimens from piglets up to 28 days were examined to determine the presence of sapovirus genome by RT-PCR assay, using primers designed to amplify a 331 bp segment of the RNA polymerase gene. In 44.4% (8/18) of fecal samples, an amplified DNA fragment was obtained. One of these fragments was sequenced and submitted to molecular and phylogenetic analysis. This analysis revealed high similarity, with nucleotides (87%) and amino acids (97.8%), to the Cowden strain, the GIII prototype of porcine enteric calicivirus. This is the first description of sapovirus in Brazilian swine herds.
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SIOCHU (Α. ΣΙΩΧΟΥ), A. « Hepatitis E ». Journal of the Hellenic Veterinary Medical Society 54, no 3 (19 décembre 2017) : 236. http://dx.doi.org/10.12681/jhvms.15264.
Texte intégralRésumé :
HEV is responsible for large epidemics of acute hepatitis and sporadic cases in southeast and central Asia, the Middle East, parts of Africa and Mexico. Few HEV infections have been reported in non-travelers in industrialized countries, including the Netherlands. HEV infection spreads by the fecal-oral route, usually through contaminated water. The clinical illness resembles other forms of acute viral hepatitis, with onset after an incubation period of one to eight weeks. Clinical attack rates are the highest among young adults. In younger age groups, infections are more often anicteric and asymptomatic. Chronic HEV infection has not been observed. Although the death rate is usually low (0.07% to 0.6%), the illness may be particularly severe among pregnant women, with death rates as high as 25%. To date, no specific treatment is available for HEV infection. Ensuring a clean drinking water supply remains the best preventive strategy. HEV is a small, non-enveloped virus that has apositive-sense, single-stranded RNA genome of approximately 7.2 Kb. The genome contains three open reading frames (ORFs). In general, different genotypes circulate within different geographical areas, (genotype 1: Southeast and Central Asia, genotype 2: Mexico, genotype 3: USA-US1,US2 , SwUS and genotype 4: China). HEV was initially considered to be a member of the family Caliciviridae. However, on the basis of comparative phylogenetic analysis, it was recendy removed from the Caliciviridae family. In Western Europe and the United States, clinical cases of hepatitis caused by HEV are rare and most often they have been associated with travel to areas, where HEV is endemic. However, novel strains of HEV have been isolated in the US and in Europe from patients without a history of travel to regions endemic for HEV. Serological studies in industrialized countries have shown that the prevalence of anti-HEV antibodies is 1-6% among blood donors and is much higher in some populations. The cause of this relatively high prevalence of anti-HEV in countries, where clinical hepatitis E is rare, is unknown. Balayan et al. first demonstrated that domestic pigs could be experimentally infected with a human HEV isolate. Clayson et al. subsequently detected RNA and antibodies of HEV in pigs in Nepal, but the virus was not characterized. A unique swine HEV was first isolated in 1997. Later studies revealed that swine from other countries, such as Australia, Vietnam, Taiwan, Canada, Spain and Greece, were also infected with HEV. The swine HEV strain isolated from a pig in Illinois is genetically very closely related to two U.S. strains of human HEV. Similarly, the swine HEV strains isolated from pigs in Taiwan are closely related to Taiwanese strains of human HEV. Interspecies transmission of HEV has been experimentally demonstrated: swine HEV infected non-human primates and a strain of human HEV infected pigs. Also, HEV from swine might sometimes be transmitted to humans through environmental contact. These findings implicate a possible transmission of the virus from pigs to humans. These data suggested that HEV infection of humans through contact with pigs may be possible and that swine veterinarians and other pig handlers may be at risk of zoonotic infection.
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Radzіkhovskyі, N., О. Dyshkant, O. Tolokevich et V. Moshkivsky. « EPIZOOTOLOGICAL FEATURES CORONAVIRUS INFECTION IN CATS ». Scientific and Technical Bulletin оf State Scientific Research Control Institute of Veterinary Medical Products and Fodder Additives аnd Institute of Animal Biology 22, no 2 (7 octobre 2021) : 317–22. http://dx.doi.org/10.36359/scivp.2021-22-2.37.
Texte intégralRésumé :
The exact number of cats living on our planet is unknown, but there are reports with reference to studies conducted by French scientists from the University of Lyon (France) in 400 million domestic cats, most of which live in the United States and Brazil (93 and about 100 million. in accordance). However, according to researchers, the first place in the world in terms of the number of cats per capita is Australia (ratio of 9:10), and Ukraine is in the top 10 countries with the largest number of domestic cats.
In the mid-90s of the twentieth century, Ukraine faced a new infectious disease that affects different species of the feline family - infectious feline peritonitis (IPC), the causative agent of which is a virus of the family Coronaviridae. Animal coronaviruses have been a problem for more than 50 years, however, given their variability and large diversity, the study of this group of viruses continues today.
The article presents data on the epizootological features of coronavirus infection in cats for the period 2019 - 2020 in veterinary clinics in Zhytomyr and Kyiv. During a certain period of time, during the experiment, 115 samples were taken for the study, of which 95 animals were detected with the virus of the family Coronaviridae.
The paper highlights the results of the study of age and breed predisposition. It has been found that 2-6 month old kittens are most prone, especially breeds such as British, Persian and Scottish. Indicators of seasonality of manifestation, and also dynamics of morbidity of cats with a coronavirus infection are resulted. In the spring and summer, the peak incidence of the studied disease was noted.
According to the results of the epizootic analysis, a nosological profile of infectious diseases in cats was formed, which is represented by 8 infections, and the most frequently registered diseases are caused by viruses of the families Herpesviridae Caliciviridae and Parvoviridae.
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Levenson, Eric Andrew, Craig Martens, Kishore Kanakabandi, Charles Turner, Stanislav V. Sosnovtsev, Stacey Ricklefs, Stephen Porcella et Kim Y. Green. « The host response to murine norovirus infection induces significant engagement of IFN and TNF-a immunological programs ». Journal of Immunology 198, no 1_Supplement (1 mai 2017) : 158.2. http://dx.doi.org/10.4049/jimmunol.198.supp.158.2.
Texte intégralRésumé :
Abstract Norovirus, a positive stranded RNA virus in the family Caliciviridae, is a major cause of acute gastroenteritis. Outbreaks occur primarily in locations such as schools, nursing homes, and cruise ships where individuals are in close proximity. An acute norovirus infection can become chronic in immunocompromised individuals, and an effective antiviral drug is needed. The 7.5 kb genome encodes a polyprotein in ORF1 that is co-translationally cleaved by the viral protease into six nonstructural proteins. The two structural proteins, VP1 and VP2, are encoded in ORF2 and ORF3, respectively. The viral proteins mediate replication and packaging of the genome into icosahedral capsids. The host cell provides additional proteins and building blocks for replication, but only a few essential host factors have been elucidated. To gain insight into the host response to norovirus infection, we performed next generation sequencing-based RNA sequencing on murine macrophages infected with murine norovirus. We obtained RNA from a time course of infection at 0, 8, 14, and 20 hours post infection with mock infections at 0 and 20 hours. Analysis of the host transcriptome reveals full activation of cellular immune response pathways, with NF-kβ, STAT1, and STAT3-based signaling evident. In addition, we observed transcriptional evidence of IRF3 activation with a transition to IRF3/IRF7 signaling. TNF-a-based activation is also clear with most downstream effectors up-regulated. These observations correlate well with the known cytokine response from patient serum samples, disease progression, and symptomatology of human norovirus. We are currently applying these findings toward drug discovery efforts.
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Di Profio, Federica, Vittorio Sarchese, Paola Fruci, Giovanni Aste, Vito Martella, Andrea Palombieri et Barbara Di Martino. « Exploring the Enteric Virome of Cats with Acute Gastroenteritis ». Veterinary Sciences 10, no 5 (18 mai 2023) : 362. http://dx.doi.org/10.3390/vetsci10050362.
Texte intégralRésumé :
Viruses are a major cause of acute gastroenteritis (AGE) in cats, chiefly in younger animals. Enteric specimens collected from 29 cats with acute enteritis and 33 non-diarrhoeic cats were screened in PCRs and reverse transcription (RT) PCR for a large panel of enteric viruses, including also orphan viruses of recent identification. At least one viral species, including feline panleukopenia virus (FPV), feline enteric coronavirus (FCoV), feline chaphamaparvovirus, calicivirus (vesivirus and novovirus), feline kobuvirus, feline sakobuvirus A and Lyon IARC polyomaviruses, was detected in 66.1% of the samples.. Co-infections were mainly accounted for by FPV and FCoV and were detected in 24.2% of the samples. The virome composition was further assessed in eight diarrhoeic samples, through the construction of sequencing libraries using a sequence-independent single-primer amplification (SISPA) protocol. The libraries were sequenced on Oxford Nanopore Technologies sequencing platform. A total of 41 contigs (>100 nt) were detected from seven viral families infecting mammals, included Parvoviridae, Caliciviridae, Picornaviridae, Polyomaviridae, Anelloviridae, Papillomaviridae and Paramyxoviridae, revealing a broad variety in the composition of the feline enteric virome.
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Sharif, Muhammad, Yeong-Bin Baek, Thu Ha Nguyen, Mahmoud Soliman et Kyoung-Oh Cho. « Porcine sapovirus-induced RIPK1-dependent necroptosis is proviral in LLC-PK cells ». PLOS ONE 18, no 2 (3 février 2023) : e0279843. http://dx.doi.org/10.1371/journal.pone.0279843.
Texte intégralRésumé :
Sapoviruses belonging to the genus Sapovirus within the family Caliciviridae are commonly responsible for severe acute gastroenteritis in both humans and animals. Caliciviruses are known to induce intrinsic apoptosis in vitro and in vivo, however, calicivirus-induced necroptosis remains to be fully elucidated. Here, we demonstrate that infection of porcine kidney LLC-PK cells with porcine sapovirus (PSaV) Cowden strain as a representative of caliciviruses induces receptor-interacting protein kinase 1 (RIPK1)-dependent necroptosis and acts as proviral compared to the antiviral function of PSaV-induced apoptosis. Infection of LLC-PK cells with PSaV Cowden strain showed that the interaction of phosphorylated RIPK1 (pRIPK1) with RIPK3 (pRIPK3), mixed lineage kinase domain-like protein (pMLKL) increased in a time-dependent manner, indicating induction of PSaV-induced RIPK1-dependent necroptosis. Interfering of PSaV-infected cells with each necroptotic molecule (RIPK1, RIPK3, or MLKL) by treatment with each specific chemical inhibitor or knockdown with each specific siRNA significantly reduced replication of PSaV but increased apoptosis and cell viability, implying proviral action of PSaV-induced necroptosis. In contrast, treatment of PSaV-infected cells with pan-caspase inhibitor Z-VAD-FMK increased PSaV replication and necroptosis, indicating an antiviral action of PSaV-induced apoptosis. These results suggest that PSaV-induced RIPK1-dependent necroptosis and apoptosis‒which have proviral and antiviral effects, respectively‒counterbalanced each other in virus-infected cells. Our study contributes to understanding the nature of PSaV-induced necroptosis and apoptosis and will aid in developing efficient and affordable therapies against PSaV and other calicivirus infections.
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Buckow, Roman, Sonja Isbarn, Dietrich Knorr, Volker Heinz et Anselm Lehmacher. « Predictive Model for Inactivation of Feline Calicivirus, a Norovirus Surrogate, by Heat and High Hydrostatic Pressure ». Applied and Environmental Microbiology 74, no 4 (21 décembre 2007) : 1030–38. http://dx.doi.org/10.1128/aem.01784-07.
Texte intégralRésumé :
ABSTRACT Noroviruses, which are members of the Caliciviridae family, represent the leading cause of nonbacterial gastroenteritis in developed countries; such norovirus infections result in high economic costs for health protection. Person-to-person contact, contaminated water, and foods, especially raw shellfish, vegetables, and fruits, can transmit noroviruses. We inactivated feline calicivirus, a surrogate for the nonculturable norovirus, in cell culture medium and mineral water by heat and high hydrostatic pressure. Incubation at ambient pressure and 75°C for 2 min as well as treatment at 450 MPa and 15°C for 1 min inactivated more than 7 log10 PFU of calicivirus per ml in cell culture medium or mineral water. The heat and pressure time-inactivation curves obtained with the calicivirus showed tailing in the logarithmic scale. Modeling by nth-order kinetics of the virus inactivation was successful in predicting the inactivation of the infective virus particles. The developed model enables the prediction of the calicivirus reduction in response to pressures up to 500 MPa, temperatures ranging from 5 to 75°C, and various treatment times. We suggest high pressure for processing of foods to reduce the health threat posed by noroviruses.
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Catella, Cristiana, Francesco Pellegrini, Alice Carbonari, Matteo Burgio, Giovanni Patruno, Annalisa Rizzo, Claudia Maria Trombetta et al. « In Vitro Antiviral and Virucidal Activity of Ozone against Feline Calicivirus ». Animals 14, no 5 (22 février 2024) : 682. http://dx.doi.org/10.3390/ani14050682.
Texte intégralRésumé :
The Caliciviridae family includes several viral pathogens of humans and animals, including norovirus (NoV), genus Norovirus, and feline calicivirus (FCV), genus Vesivirus. Due to their resistance in the environment, NoV and FCV may give rise to nosocomial infections, and indirect transmission plays a major role in their diffusion in susceptible populations. A pillar of the control of viruses resistant to an environment is the adoption of prophylaR1.6ctic measures, including disinfection. Since NoVs are not cultivatable in common cell cultures, FCV has been largely used as a surrogate of NoV for the assessment of effective disinfectants. Ozone (O3), a molecule with strong oxidizing properties, has shown strong microbicidal activity on bacteria, fungi, protozoa, and viruses. In this study, the virucidal and antiviral activities of an O3/O2 gas mixture containing O3 were tested at different concentrations (20, 35, and 50 μg/mL) for distinct contact times against FCV. The O3/O2 gas mixture showed virucidal and antiviral activities against FCV in a dose- and contact time-dependent fashion. Ozonation could be considered as a valid strategy for the disinfection of environments at risk of contamination by FCV and NoV.
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Sawaswong, Vorthon, Elizabeth Fahsbender, Eda Altan, Taratorn Kemthong, Xutao Deng, Suchinda Malaivijitnond, Sunchai Payungporn et Eric Delwart. « High Diversity and Novel Enteric Viruses in Fecal Viromes of Healthy Wild and Captive Thai Cynomolgus Macaques (Macaca fascicularis) ». Viruses 11, no 10 (22 octobre 2019) : 971. http://dx.doi.org/10.3390/v11100971.
Texte intégralRésumé :
Cynomolgus macaques are common across South East Asian countries including Thailand. The National Primate Research Center of Thailand, Chulalongkorn University (NPRCT-CU) captures wild-borne cynomolgus macaque for research use. Limited information is available on the enteric viruses and possible zoonotic infections into or from cynomolgus macaques. We characterized and compare the fecal virome of two populations; healthy wild-originated captive cynomolgus macaques (n = 43) reared in NPRCT-CU and healthy wild cynomolgus macaques (n = 35). Over 90% of recognized viral sequence reads amplified from feces were from bacterial viruses. Viruses from seven families of mammalian viruses were also detected (Parvoviridae, Anelloviridae, Picornaviridae, Adenoviridae, Papillomaviridae, Herpesviridae, and Caliciviridae). The genomes of a member of a new picornavirus genus we named Mafapivirus, a primate chapparvovirus, and a circular Rep-encoding single-strand (CRESS) DNA virus were also characterized. Higher abundance of CRESS DNA viruses of unknown tropism and invertebrate-tropic ambidensovirus were detected in wild versus captive macaques likely reflecting dietary differences. Short term rearing in captivity did not have a pronounced effect on the diversity of mammalian viruses of wild cynomolgus macaques. This study is the first report of the fecal virome of cynomolgus macaques, non-human primates frequently used in biomedical research and vaccination studies.
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SIMÕES, R.S.Q. « Environmental virology linked to waterborne diseases and foodborne pathogens : Human and animal food viruses ». International Journal of Frontiers in Biology and Pharmacy Research 5, no 1 (30 mars 2024) : 049–56. http://dx.doi.org/10.53294/ijfbpr.2024.5.1.0031.
Texte intégralRésumé :
Foodborne illnesses constitute a serious global one health issue. The transmission of foodborne viruses can occur due to inadequate hygiene of food, lack of basic sanitation, poor personal hygiene and consumption of raw or undercooked food. This study aims overview about environmental virology linked to waterborne diseases and foodborne pathogens in human and animal food viruses. Thus, epidemiological studies have proposed some emerging pathogens as possible transmitters of contaminated water ingestion based on biochemical properties and viral structures such as: Picornaviridae (polioviruses, enteroviruses, coxsakiviruses, hepatitis A viruses and echoviruses), Adenoviridae (adenoviruses), Caliciviridae (noroviruses, caliciviruses, astroviruses), and Reoviridae (reoviruses and rotaviruses). These viruses can cause gastrointestinal, liver and central nervous system disorders. In controlling foodborne infections, accurately identifying sources of contamination is a significant challenge, given the complexity of the food production chain. The lack of adequate monitoring and neglect of good health practices contribute to the spread of these infections. Large-scale immunization has contributed to the reduction of enteric outbreaks and eradication of cases in many regions of the world as a prevention of hepatitis A and poliomyelitis. However, challenges such as the lack of effectiveness in inspecting viruses in food increase the risk of outbreaks and epidemics, with emphasis on Noroviruses as the main causes of these infections today. Investment in vaccine research and development has been a fundamental strategy to reduce these statistics, especially in vulnerable groups. Moreover, the implementation molecular-based tools and wastewater-based epidemiology studies to high-throughput for aquatic biomonitoring should be up to date to avoid the risk and impact on public health and aquatic environments. Novel perspectives to control of waterborne viruses has been introduced in continuous surveillance programs for ecosystems monitoring.
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Fitzner, Andrzej, et Wiesław Niedbalski. « Diversity of RHD virus : epidemiological, diagnostic and immunological importance ». Medycyna Weterynaryjna 73, no 12 (2017) : 811–18. http://dx.doi.org/10.21521/mw.5815.
Texte intégralRésumé :
Rabbit haemorrhagic disease (RHD) was first recognized in China in 1984. In Europe, the disease appeared in 1986 in Italy, and in the following years RHD was observed in many other European countries, including Poland in 1988. The disease is caused by RHD virus (RHDV), classified as a representative of the Lagovirus genus within the Caliciviridae family. Lagoviruses include the non-pathogenic rabbit calicivirus (RCV) and the European brown hare syndrome virus (EBHSV). There are three basic variants (subtypes) of pathogenic RHD viruses: classic (RHDV) and antigenic subtypes RHDVa and RHDV2 (RHDVb), distinguished on the basis of epidemiological characteristics, infectious properties and antigenic and genetic modifications. Phylogenetic analysis of RHDV revealed the presence of five genogroups (G1-G5) with similar time of isolation, regardless of the place of occurrence. RHDVa strains are genetically more variable than RHDV, and all RHDVa strains belong to genogroup G6. RHDV2 was diagnosed for the first time in 2010 in domestic and wild rabbits in France, and later in the Iberian Peninsula, and it was called RHDVb. Like the previously identified variants of the RHD virus, RHDV2 spreads to other regions of the world, and in 2011-2016 it was diagnosed in many European countries, North America, Africa and Australia. Strains of RHD2 form a separate, uniform phylogenetic group and are more similar to the non-pathogenic rabbit calicivirus than to pathogenic RHDV and RHDVa. Infections with different variants of RHD viruses are a serious epidemiological, diagnostic and immunological problem. Advanced antigenic changes in RHD viruses limit the usefulness of standard RHD vaccines in controlling the disease....
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Farkas, Tibor, Robert W. Cross, Edwin Hargitt, Nicholas W. Lerche, Ardythe L. Morrow et Karol Sestak. « Genetic Diversity and Histo-Blood Group Antigen Interactions of Rhesus Enteric Caliciviruses ». Journal of Virology 84, no 17 (16 juin 2010) : 8617–25. http://dx.doi.org/10.1128/jvi.00630-10.
Texte intégralRésumé :
ABSTRACT Recently, we reported the discovery and characterization of Tulane virus (TV), a novel rhesus calicivirus (CV) (T. Farkas, K. Sestak, C. Wei, and X. Jiang, J. Virol. 82:5408-5416, 2008). TV grows well in tissue culture, and it represents a new genus within Caliciviridae, with the proposed name of Recovirus. We also reported a high prevalence of CV antibodies in macaques of the Tulane National Primate Research Center (TNPRC) colony, including anti-norovirus (NoV), anti-sapovirus (SaV), and anti-TV (T. Farkas, J. Dufour, X. Jiang, and K. Sestak, J. Gen. Virol. 91:734-738, 2010). To broaden our knowledge about CV infections in captive nonhuman primates (NHP), 500 rhesus macaque stool samples collected from breeding colony TNPRC macaques were tested for CVs. Fifty-seven (11%) samples contained recovirus isolates. In addition, one NoV was detected. Phylogenetic analysis classified the recovirus isolates into two genogroups and at least four genetic types. The rhesus NoV isolate was closely related to GII human NoVs. TV-neutralizing antibodies were detected in 88% of serum samples obtained from primate caretakers. Binding and plaque reduction assays revealed the involvement of type A and B histo-blood group antigens (HBGA) in TV infection. Taken together, these findings indicate the zoonotic potential of primate CVs. The discovery of a genetically diverse and prevalent group of primate CVs and remarkable similarities between rhesus enteric CVs and human NoVs opens new possibilities for research involving in vitro and in vivo models of human NoV gastroenteritis.
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Kalinina, O. S. « Viruses in food products ». Scientific Messenger of LNU of Veterinary Medicine and Biotechnologies 23, no 103 (27 novembre 2021) : 15–20. http://dx.doi.org/10.32718/nvlvet10303.
Texte intégralRésumé :
Data on viral food contaminants that are actually or potentially capable of realizing the food route of infection are presented. The main sources of infection of food with viruses are named: human waste / faeces, contaminated food processing facilities, animals-carriers of zooanthroponotic infections. The groups of viruses transmitted through food are characterized: 1) gastroenteritis pathogens – Sapporo and Norwalk viruses from the family Caliciviridae; Rotavirus A from the family Reoviridae; Mammastroviruses 1, 6, 8 and 9 from the family Astroviridae; Human mastadenovirus F from the family Adenoviridae; Aichivirus A from the family Picornaviridae; 2) Hepatovirus A from the family Picornaviridae and Orthohepevirus A from the family Hepeviridae (with replication in the liver); 3) viruses with replication in the human intestine, which after generalization of the infection affect the CNS – Еnteroviruses B and C from the family Picornaviridae. The stability and survival time of viruses in the environment and food are shown. The main ways of transmission of viruses that are able to enter the human body through infected foods are considered. Influenza A (H1N1) virus has been identified as a possible contaminant in pork and chicken, which without heat treatment can pose a potential risk of human infection. The ability of classical and African swine fever pathogens to remain viable after industrial processing of meat or raw meat has been shown. Families of viruses whose zoopathogenic representatives can contaminate meat products (beef, pork, chicken) are named: Parvoviridae, Anelloviridae, Circoviridae, Polyomaviridae, Smacoviridae. To determine the possible latent infection of people with these viruses, it is necessary to test sera for the presence of specific antibodies. The detection of gyroviruses of the family Anelloviridae and huchismacoviruses of the family Smacoviridae in human faeces may be due to the consumption of infected chicken meat. Data on extraction and concentration methods and methods of virus detection in contaminated food products: PCR (reverse transcription and real-time), ELISA, IСA, electron microscopy, virus isolation in transplanted cell cultures with subsequent identification in serological reactions, NR, IFА, ELISA) or PCR.
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Leuthold, Mila M., Kevin P. Dalton et Grant S. Hansman. « Structural Analysis of a Rabbit Hemorrhagic Disease Virus Binding to Histo-Blood Group Antigens ». Journal of Virology 89, no 4 (10 décembre 2014) : 2378–87. http://dx.doi.org/10.1128/jvi.02832-14.
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ABSTRACTRabbit hemorrhagic disease virus (RHDV) is a member of theCaliciviridaefamily (Lagovirusgenus). RHDV is highly contagious and attaches to epithelial cells in the digestive or respiratory tract, leading to massive lesions with high mortality rates. A new variant of RHDV (termed RHDVb) recently has emerged, and previously vaccinated rabbits appear to have little protection against this new strain. Similar to human norovirus (Caliciviridae,Norovirusgenus), RHDV binds histo-blood group antigens (HBGAs), and this is thought to be important for infection. Here, we report the HBGA binding site on the RHDVb capsid-protruding domain (P domain) using X-ray crystallography. The HBGA binding pocket was located in a negatively charged patch on the side of the P domain and at a dimeric interface. Residues from both monomers contributed to the HBGA binding and involved a network of direct hydrogen bonds and water-mediated interactions. An amino acid sequence alignment of different RHDV strains indicated that the residues directly interacting with the ABH-fucose of the HBGAs (Asp472, Asn474, and Ser479) were highly conserved. This result suggested that different RHDV strains also could bind HBGAs at the equivalent pocket. Moreover, several HBGA binding characteristics between RHDVb and human genogroup II norovirus were similar, which indicated a possible convergent evolution of HBGA binding interactions. Further structural studies with other RHDV strains are needed in order to better understand the HBGA binding mechanisms among the diverse RHDV strains.IMPORTANCEWe identified, for the first time, the HBGA binding site on an RHDVb P domain using X-ray crystallography. Our results showed that RHDVb and human genogroup II noroviruses had similar HBGA binding interactions. Recently, it was discovered that synthetic HBGAs or HBGA-expressing enteric bacteria could enhance human genogroup II norovirus infection in B cells. Considering that RHDVb and genogroup II norovirus similarly interacted with HBGAs, it may be possible that a comparable cell culture system also could work with RHDVb. Taken together, these new findings will extend our understanding of calicivirus HBGA interactions and may help to elucidate the specific roles of HBGAs in calicivirus infections.
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Wasniewski, Marine, Franck Boué, Céline Richomme, Etienne Simon-Lorière, Sylvie Van der Werf, Flora Donati, Vincent Enouf et al. « Investigations into SARS-CoV-2 and other coronaviruses on mink farms in France late in the first year of the COVID-19 pandemic ». PLOS ONE 18, no 8 (25 août 2023) : e0290444. http://dx.doi.org/10.1371/journal.pone.0290444.
Texte intégralRésumé :
Soon after the beginning of the COVID-19 pandemic in early 2020, the Betacoronavirus SARS-CoV-2 infection of several mink farms breeding American minks (Neovison vison) for fur was detected in various European countries. The risk of a new reservoir being formed and of a reverse zoonosis from minks quickly became a major concern. The aim of this study was to investigate the four French mink farms to see whether SARS-CoV-2 was circulating there in late 2020. The investigations took place during the slaughtering period, thus facilitating different types of sampling (swabs and blood). On one of the four mink farms, 96.6% of serum samples were positive when tested with a SARS-CoV-2 ELISA coated with purified N protein recombinant antigen, and 54 out of 162 (33%) pharyngo-tracheal swabs were positive by RT-qPCR. The genetic variability among 12 SARS-CoV-2 genomes sequenced from this farm indicated the co-circulation of several lineages at the time of sampling. All the SARS-CoV-2 genomes detected were nested within the 20A clade (Nextclade), together with SARS-CoV-2 genomes from humans sampled during the same period. The percentage of SARS-CoV-2 seropositivity by ELISA varied between 0.3 and 1.1% on the other three farms. Interestingly, among these three farms, 11 pharyngo-tracheal swabs and 3 fecal pools from two farms were positive by end-point RT-PCR for an Alphacoronavirus very similar to a mink coronavirus sequence observed on Danish farms in 2015. In addition, a mink Caliciviridae was identified on one of the two farms positive for Alphacoronavirus. The clinical impact of these inapparent viral infections is not known. The co-infection of SARS-CoV-2 with other viruses on mink farms could help explain the diversity of clinical symptoms noted on different infected farms in Europe. In addition, the co-circulation of an Alphacoronavirus and SARS-CoV-2 on a mink farm would potentially increase the risk of viral recombination between alpha and betacoronaviruses as already suggested in wild and domestic animals, as well as in humans.
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Smiley, J. R., K. O. Chang, J. Hayes, J. Vinjé et L. J. Saif. « Characterization of an Enteropathogenic Bovine Calicivirus Representing a Potentially New Calicivirus Genus ». Journal of Virology 76, no 20 (15 octobre 2002) : 10089–98. http://dx.doi.org/10.1128/jvi.76.20.10089-10098.2002.
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ABSTRACT Bovine enteric caliciviruses (BEC) are associated with diarrhea in young calves. The BEC strains detected in Europe form a third genogroup within the genus “Norwalk-like viruses” (NLV) of the family Caliciviridae. In this report, we present sequence, clinical, and histological data characterizing a novel enteropathogenic BEC strain, NB, detected in fecal specimens from calves in the United States. The complete RNA genome of the NB virus is 7,453 bases long and is organized into two open reading frames (ORFs). ORF-1 is 2,210 amino acids long and encodes a large nonstructural polyprotein contiguous with the major capsid protein (VP1), similar to the lagoviruses and “Sapporo-like viruses” (SLV). The conserved calicivirus motifs were identified in the nonstructural proteins. ORF-2 is located at the 3′ end of the genome and encodes a small basic protein (VP2) of 225 amino acids. The 5′ and 3′ untranslated regions are 74 and 67 bases long, respectively. Among caliciviruses, NB virus shows amino acid identities of 14.1 to 22.6% over the entire ORF-1 nonstructural-protein sequence with NLV, SLV, vesivirus, and lagovirus strains, while the overall sequence identity of the complete NB VP-1 with other caliciviruses is low, varying between 14.6 and 26.7%. Phylogenetic analysis of the complete VP1 protein, including strains from all four calicivirus genera, showed the closest grouping of NB virus to be with viruses in the genus Lagovirus, which cause liver infections and systemic hemorrhage in rabbits. In gnotobiotic calves, however, NB virus elicited only diarrhea and intestinal lesions that were most severe in the upper small intestine (duodenum and jejunum), similar to the NLV BEC strains. The tissues of major organs, including the lung, liver, kidney, and spleen, had no visible microscopic lesions.
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Lambden, Paul R., et Ian N. Clarke. « Genome organization in the caliciviridae ». Trends in Microbiology 3, no 7 (juillet 1995) : 261–65. http://dx.doi.org/10.1016/s0966-842x(00)88940-4.
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Lewis, Charlotte B., Lee Sherry, Michaela J. Conley, Masaaki Nakashima, Shirin Akbar, Nithya Govindan, Margaret J. Hosie et David Bhella. « Conformational Flexibility in Capsids Encoded by the Caliciviridae ». Viruses 16, no 12 (26 novembre 2024) : 1835. http://dx.doi.org/10.3390/v16121835.
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Caliciviruses are a diverse group of non-enveloped, positive-sense RNA viruses with a wide range of hosts and transmission routes. Norovirus is the most well-known member of the Caliciviridae; the acute gastroenteritis caused by human norovirus (HuNoV), for example, frequently results in closures of hospital wards and schools during the winter months. One area of calicivirus biology that has gained increasing attention over the past decade is the conformational flexibility exhibited by the protruding (P) domains of the major capsid protein VP1. This was observed in structure analyses of capsids encoded by many species and is often a consequence of environmental cues such as metal ions, changes to pH, or receptor/co-factor engagement. This review summarises the current understanding of P-domain flexibility, discussing the role this region plays in caliciviral infection and immune evasion, and highlighting potential avenues for further investigation.
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Eruera, Alice-Roza, Alice M. McSweeney, Geena M. McKenzie-Goldsmith et Vernon K. Ward. « Protein Nucleotidylylation in +ssRNA Viruses ». Viruses 13, no 8 (5 août 2021) : 1549. http://dx.doi.org/10.3390/v13081549.
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Nucleotidylylation is a post-transcriptional modification important for replication in the picornavirus supergroup of RNA viruses, including members of the Caliciviridae, Coronaviridae, Picornaviridae and Potyviridae virus families. This modification occurs when the RNA-dependent RNA polymerase (RdRp) attaches one or more nucleotides to a target protein through a nucleotidyl-transferase reaction. The most characterized nucleotidylylation target is VPg (viral protein genome-linked), a protein linked to the 5′ end of the genome in Caliciviridae, Picornaviridae and Potyviridae. The nucleotidylylation of VPg by RdRp is a critical step for the VPg protein to act as a primer for genome replication and, in Caliciviridae and Potyviridae, for the initiation of translation. In contrast, Coronaviridae do not express a VPg protein, but the nucleotidylylation of proteins involved in replication initiation is critical for genome replication. Furthermore, the RdRp proteins of the viruses that perform nucleotidylylation are themselves nucleotidylylated, and in the case of coronavirus, this has been shown to be essential for viral replication. This review focuses on nucleotidylylation within the picornavirus supergroup of viruses, including the proteins that are modified, what is known about the nucleotidylylation process and the roles that these modifications have in the viral life cycle.
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Kar, Premashis. « HEV-related Liver Disease in India : Why is the Disease Stormy ? » Annals of the National Academy of Medical Sciences (India) 54, no 01 (janvier 2018) : 054–61. http://dx.doi.org/10.1055/s-0040-1712822.
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ABSTRACTHepatitis E virus (HEV) is an important cause of epidemic and sporadic acute viral hepatitis (AVH) in many developing countries, including India. Hepatitis E, a positive-sense single-stranded RNA virus approximately 7.2 kb in length had been classified provisionally into the Caliciviridae family from 1988 to 1998 but HEV is currently placed in the genus Hepevirus and is the only member of the family Hepeviridae. Pregnant women with jaundice and AVH caused by HEV infection have worse fetal and obstetric outcome and higher maternal mortality compared to other types of viral hepatitis. Studies from various developing countries have shown that the incidence of HEV infection in pregnancy is high and a significant proportion of pregnant women can progress to fulminant hepatitis with a mortality rate varying from 30% to 100%. The incidence of hepatitis B virus (HBV) related acute liver failure is known widely in comparison to hepatitis C virus (HCV) infection in which acute liver failure (ALF) is rare. But the severe course of HEV infection causing ALF during pregnancy is unique to this virus with chronicity occurring in recipients of solid organ transplants.Various factors have been suggested to be associated with the mortality rate of the HEV in pregnant women along with the abortion of the fetus. Steroid hormones play a significant role in the viral replication through their effects on viral regulatory elements. The NF-κB signaling pathway regulating at the transcriptional level through p50 subunits has been suggested to correlate with the severe liver damage, leading to multiple organ failure and the death of both the mother and the fetus. Pregnant women in Asia suffer from folate deficiency reducing the immunocompetence to greater risk of multiple viral infections and higher viral load. The viral load of HEV was found to be significantly higher (P < 0.05) in pregnant patients compared to the non-pregnant and the viral copies of HEV with fulminant hepatic failure (FHF) in pregnant women were comparatively higher when compared to the pregnant women with AVH, which may be related to the severity of the disease in these patients. Besides, reduced expression of progesterone and progesterone induced-blocking factor and the high viral load of HEV have been regarded as a cause of poor pregnancy outcome in hepatitis E infection. Vertical transmission of the HEV infection has been reported. There are published reports of abortion, death of the fetus in utero, premature delivery or death of the baby soon after birth in patients with icteric hepatitis or with ALF caused by HEV. However, studies in Europe and United States have shown the course of viral hepatitis during pregnancy resembling with the non-pregnant women. In contrast, various reports carried out in India, Iran, Africa, and Middle East have reported the incidence of ALF to be higher during pregnancy.Data on the viral load of HEV during pregnancy are limited. The study was designed to determine the viral load of HEV and its association with the disease severity in patients with ALF. A total HEV related 163 patients with ALF which included 105 pregnant, 46 non-pregnant women and girls, 12 men, and 730 patients with AVH which comprised of 220 pregnant women; 282 non-pregnant women and girls, and 228 men were included. Viral load was measured by real-time PCR. Comparison was made between the pregnant and non-pregnant women. HEV RNA was detectable in 265 patients (142 pregnant; 75 non-pregnant and 48 men) and 104 patients with ALF (64 pregnant, 34 non-pregnant and 6 men). The viral load of HEV in pregnant women with ALF and AVH was significantly higher 129,984.0±103,104.17 and 768.92±1,105.40 copies/ml, respectively compared to the non-pregnant women which was 189.2±225 and 12.73±7.8 copies/ml (P < 0.0001). The viral load of HEV was also significantly higher in the pregnant patients with ALF compared to the pregnant women with AVH and also men (P < 0.0001). High viral load of HEV during pregnancy could be one of the factors responsible for the severity of the infection during pregnancy.
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Chaudhry, Yasmin, Michael A. Skinner et Ian G. Goodfellow. « Recovery of genetically defined murine norovirus in tissue culture by using a fowlpox virus expressing T7 RNA polymerase ». Journal of General Virology 88, no 8 (1 août 2007) : 2091–100. http://dx.doi.org/10.1099/vir.0.82940-0.
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Despite the significant disease burden caused by human norovirus infection, an efficient tissue-culture system for these viruses remains elusive. Murine norovirus (MNV) is an ideal surrogate for the study of norovirus biology, as the virus replicates efficiently in tissue culture and a low-cost animal model is readily available. In this report, a reverse-genetics system for MNV is described, using a fowlpox virus (FWPV) recombinant expressing T7 RNA polymerase to recover genetically defined MNV in tissue culture for the first time. These studies demonstrated that approaches that have proved successful for other members of the family Caliciviridae failed to lead to recovery of MNV. This was due to our observation that vaccinia virus infection had a negative effect on MNV replication. In contrast, FWPV infection had no deleterious effect and allowed the recovery of infectious MNV from cells previously transfected with MNV cDNA constructs. These studies also indicated that the nature of the 3′-terminal nucleotide is critical for efficient virus recovery and that inclusion of a hepatitis delta virus ribozyme at the 3′ end can increase the efficiency with which virus is recovered. This system now allows the recovery of genetically defined noroviruses and will facilitate the analysis of the effects of genetic variation on norovirus pathogenesis.
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DEY, S. K., O. PHATHAMMAVONG, T. D. NGUYEN, A. THONGPRACHUM, W. CHAN-IT, S. OKITSU, M. MIZUGUCHI et H. USHIJIMA. « Seasonal pattern and genotype distribution of sapovirus infection in Japan, 2003–2009 ». Epidemiology and Infection 140, no 1 (4 mars 2011) : 74–77. http://dx.doi.org/10.1017/s0950268811000240.
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SUMMARYSapovirus, a member of the family Caliciviridae, is one of the major causative agents of viral gastroenteritis affecting all age groups. A total of 3232 faecal specimens collected from infants and children with gastroenteritis in five different regions of Japan during 2003–2009 were examined for sapovirus by reverse transcription–polymerase chain reaction. Sapoviruses were detected in 131 (4·05%) patients with the peak observed mainly in the cold season (November–March) in Japan during 2003–2009. During the last 6 years, sapovirus GI/1 was the predominant strain in Japan followed by GIV, GII/3, GII/6, GII/2, GII/12 and GI, respectively.
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Farkas, Tibor, Karol Sestak, Chao Wei et Xi Jiang. « Characterization of a Rhesus Monkey Calicivirus Representing a New Genus of Caliciviridae ». Journal of Virology 82, no 11 (2 avril 2008) : 5408–16. http://dx.doi.org/10.1128/jvi.00070-08.
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ABSTRACT In this study, we report the characterization of a novel calicivirus (CV), the Tulane virus (TV), which was isolated from stool samples of captive juvenile rhesus macaques (Macaca mulatta) of the Tulane National Primate Research Center. The complete genome of TV contains 6,714 nucleotides plus a poly(A) tail and is organized into three open reading frames (ORFs) that encode the nonstructural (NS) polyprotein (ORF1); the capsid protein (ORF2), with an estimated molecular mass of 57.9 kDa; and a possible minor structural protein (ORF3), with an isoelectric point (pI) of 10.0 and a calculated molecular mass of 22.8 kDa. The NS polyprotein revealed all typical CV amino acid motifs, including GXXGXGKT (NTPase), EYXEX (Vpg), GDCG (protease), and GLPSG and YGDD (polymerase). Phylogenetic trees constructed for the NS polyprotein, NTPase, protease, polymerase, and capsid protein sequences consistently placed the TV on a branch rooted with Norovirus, but with distances equal to those between other genera. The TV can be cultured in a monkey kidney cell line (LLC-MK2) with the appearance of typical cytopathic effect. TV exhibits a typical CV morphology, with a diameter of 36 nm, and has a buoyant density of 1.37 g/ml. According to these physicochemical and genetic characteristics, TV represents a new CV genus for which we propose the name “Recovirus” (rhesus enteric CV). Although the pathogenicity of TV in rhesus macaques remains to be elucidated, the likelihood of TV causing intestinal infection and the availability of a tissue culture system make this virus a valuable surrogate for human CVs.
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Davidson, Irit, Efthymia Stamelou, Ioannis A. Giantsis, Konstantinos V. Papageorgiou, Evanthia Petridou et Spyridon K. Kritas. « The Complexity of Swine Caliciviruses. A Mini Review on Genomic Diversity, Infection Diagnostics, World Prevalence and Pathogenicity ». Pathogens 11, no 4 (29 mars 2022) : 413. http://dx.doi.org/10.3390/pathogens11040413.
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Caliciviruses are single stranded RNA viruses, non-enveloped structurally, that are implicated in the non-bacterial gastroenteritis in various mammal species. Particularly in swine, viral gastroenteritis represents a major problem worldwide, responsible for significant economic losses for the pig industry. Among the wide range of viruses that are the proven or suspected etiological agents of gastroenteritis, the pathogenicity of the members of Caliciviridae family is among the less well understood. In this context, the present review presents and discusses the current knowledge of two genera belonging to this family, namely the Norovirus and the Sapovirus, in relation to swine. Aspects such as pathogenicity, clinical evidence, symptoms, epidemiology and worldwide prevalence, genomic diversity, identification tools as well as interchanging hosts are not only reviewed but also critically evaluated. Generally, although often asymptomatic in pigs, the prevalence of those microbes in pig farms exhibits a worldwide substantial increasing trend. It should be mentioned, however, that the factors influencing the symptomatology of these viruses are still far from well established. Interestingly, both these viruses are also characterized by high genetic diversity. These high levels of molecular diversity in Caliciviridae family are more likely a result of recombination rather than evolutionary or selective adaptation via mutational steps. Thus, molecular markers for their detection are mostly based on conserved regions such as the RdRp region. Finally, it should be emphasized that Norovirus and the Sapovirus may also infect other domestic, farm and wild animals, including humans, and therefore their surveillance and clarification role in diseases such as diarrhea is a matter of public health importance as well.
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Chang, Kyeong-Ok, Stanislav S. Sosnovtsev, Gaël Belliot, Qiuhong Wang, Linda J. Saif et Kim Y. Green. « Reverse Genetics System for Porcine Enteric Calicivirus, a Prototype Sapovirus in the Caliciviridae ». Journal of Virology 79, no 3 (1 février 2005) : 1409–16. http://dx.doi.org/10.1128/jvi.79.3.1409-1416.2005.
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ABSTRACT A porcine enteric calicivirus (PEC), strain Cowden in the genus Sapovirus of the Caliciviridae family, can be propagated in a porcine kidney continuous cell line (LLC-PK) in the presence of bile acids in the cell culture medium. A full-length cDNA copy of the Cowden PEC genome was cloned into a plasmid vector directly downstream from the T7 RNA polymerase promoter, and capped RNA transcripts derived from this clone were infectious when transfected into LLC-PK cells. The recovery of PEC after transfection of RNA transcripts was dependent on the presence of bile acids, consistent with our recent identification of a bile acid-mediated signaling pathway required for PEC replication (Chang et al., Proc. Natl. Acad. Sci. USA 101:8733-8788, 2004). Recovery of virus was verified by detection of PEC antigen in transfected cells by immunofluorescence and enzyme-linked immunosorbent assays, direct observation of recovered viral particles by electron microscopy, and partial sequence analysis of their genomes (first 1,070 nucleotides) to differentiate them from tissue culture-adapted parental virus. The recovered virus retained its ability to infect piglets when administered by the oral route and showed an attenuated phenotype similar to that of the tissue culture-adapted parental virus. This reverse genetics system for PEC provides a new tool to study the molecular basis of replication and pathogenesis for caliciviruses associated with diarrheal disease.
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Parker, Tracy Dewese, Noritoshi Kitamoto, Tomoyuki Tanaka, Anne M. Hutson et Mary K. Estes. « Identification of Genogroup I and Genogroup II Broadly Reactive Epitopes on the Norovirus Capsid ». Journal of Virology 79, no 12 (15 juin 2005) : 7402–9. http://dx.doi.org/10.1128/jvi.79.12.7402-7409.2005.
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ABSTRACT Norwalk virus, a member of the family Caliciviridae, is an important cause of acute epidemic nonbacterial gastroenteritis. Norwalk and related viruses are classified in a separate genus of Caliciviridae called Norovirus, which is comprised of at least three genogroups based on sequence differences. Many of the currently available immunologic reagents used to study these viruses are type specific, which limits the identification of antigenically distinct viruses in detection assays. Identification of type-specific and cross-reactive epitopes is essential for designing broadly cross-reactive diagnostic assays and dissecting the immune response to calicivirus infection. To address this, we have mapped the epitopes on the norovirus capsid protein for both a genogroup I-cross-reactive monoclonal antibody and a genogroup II-cross-reactive monoclonal antibody by use of norovirus deletion and point mutants. The epitopes for both monoclonal antibodies mapped to the C-terminal P1 subdomain of the capsid protein. Although the genogroup I-cross-reactive monoclonal antibody was previously believed to recognize a linear epitope, our results indicate that a conformational component of the epitope explains the monoclonal antibody's genogroup specificity. Identification of the epitopes for these monoclonal antibodies is of significance, as they are components in a commercially available norovirus-diagnostic enzyme-linked immunosorbent assay.
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Kemenesi, Gábor, Ákos Gellért, Bianka Dallos, Tamás Görföl, Sándor Boldogh, Péter Estók, Szilvia Marton et al. « Sequencing and molecular modeling identifies candidate members of Caliciviridae family in bats ». Infection, Genetics and Evolution 41 (juillet 2016) : 227–32. http://dx.doi.org/10.1016/j.meegid.2016.04.004.
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Saltık, Hasbi Sait, et Zehra Erdağı. « Molecular detection of feline calicivirus (FCV) in cats with oral lesions ». Mediterranean Veterinary Journal 9, no 1 (12 juin 2024) : 261–65. https://doi.org/10.24880/meditvetj.1518701.
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Feline Calicivirus (FCV) is a major cause of oral lesions in cats with respiratory tract disease (RTD). FCV is a single-stranded, positive-polarity RNA virus that encodes three open reading frames (ORFs). Active virus excretion occurs through the saliva of cats infected with FCV, which belongs to the Vesivirus genus of the Caliciviridae family. Oral mucosal lesions caused by infectious agents in RTD lead to significant impairment in the quality of life of cats. RTD, which also affects the oral mucosa, is a common problem in cats. Ten cats of different ages, breeds, and genders with ocular lesions were used in this study. At the time of sample collection, the veterinarian performed general and oral examinations on each animal. On oral examination,varying degrees of gingivitis, stomatitis, and ulceration symptoms were noted. Samples were extracted using a commercial viral nucleic acid isolation kit. Three out of ten samples (30%) were found to be positive for FCV using RT-PCR. T In conclusion, the high sensitivity, specificity, and potential for field sample testing make RT-PCR a very important and inevitable method for research and clinical diagnosis related to FCV infection in cats with oral lesions.
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Matsvay, Alina, Marina Dyachkova, Anna Sai, Valentina Burskaia, Ilya Artyushin et German Shipulin. « Complete Genome Sequence, Molecular Characterization and Phylogenetic Relationships of a Temminck’s Stint Calicivirus : Evidence for a New Genus within Caliciviridae Family ». Microorganisms 10, no 8 (29 juillet 2022) : 1540. http://dx.doi.org/10.3390/microorganisms10081540.
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Caliciviridae is a family of viral pathogens that naturally infects vertebrates, including humans, and causes a range of highly contagious infectious diseases. Caliciviruses are not well studied because of the lack of a universal approach to their cultivation; however, the development of molecular genetics and bioinformatics methods can shed light on their genetic architecture and evolutionary relationships. Here, we present and characterize the complete genome sequence of calicivirus isolated from a sandpiper—Temminck’s stint (Calidris temminckii), preliminarily named Temminck’s stint calicivirus (TsCV). Its genome is a linear, non-segmented, single-stranded (+sense) RNA with genome organization typical of avian caliciviruses. Comparative studies have shown significant divergence of the nucleotide sequence of the TsCV genome, as well as the amino acid sequence of the major capsid protein from all publicly available genomic and protein sequences, with the highest genome sequence similarity to unclassified Ruddy turnstone calicivirus A (43.68%) and the lowest pairwise divergence of the major capsid protein with unclassified goose calicivirus (57.44%). Phylogenetic analysis, as well as a comparative analysis of the homologous proteins, showed evidence of another separate genus within the Caliciviridae family—previously proposed, but not yet accepted by International Committee on Taxonomy of Viruses (ICTV)—the Sanovirus genus, which combines seven previously unclassified genomic sequences of avian caliciviruses, including the newly discovered TsCV, which we propose to consider as a separate species.
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Liu, Guangliang, Shannon M. Kahan, Yali Jia et Stephanie M. Karst. « Primary High-Dose Murine Norovirus 1 Infection Fails To Protect from Secondary Challenge with Homologous Virus ». Journal of Virology 83, no 13 (29 avril 2009) : 6963–68. http://dx.doi.org/10.1128/jvi.00284-09.
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ABSTRACT Human noroviruses in the Caliciviridae family are the major cause of nonbacterial epidemic gastroenteritis worldwide. Primary human norovirus infection does not elicit lasting protective immunity, a fact that could greatly affect the efficacy of vaccination strategies. Little is known regarding the pathogenesis of human noroviruses or the immune responses that control them because there has previously been no small-animal model or cell culture system of infection. Using the only available small-animal model of norovirus infection, we found that primary high-dose murine norovirus 1 (MNV-1) infection fails to afford protection against a rechallenge with a homologous virus. Thus, MNV-1 represents a valuable model with which to dissect the pathophysiological basis for the lack of lasting protection against human norovirus infection. Interestingly, the magnitude of protection afforded by a primary MNV-1 infection inversely correlates with the inoculum dose. Future studies will elucidate the mechanisms by which noroviruses avoid the induction of protective immunity and the role played by the inoculum dose in this process, ultimately translating this knowledge into successful vaccination approaches.
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Natoni, Alessandro, George E. N. Kass, Michael J. Carter et Lisa O. Roberts. « The mitochondrial pathway of apoptosis is triggered during feline calicivirus infection ». Journal of General Virology 87, no 2 (1 février 2006) : 357–61. http://dx.doi.org/10.1099/vir.0.81399-0.
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Feline calicivirus (FCV) belongs to the family Caliciviridae and is an important pathogen of the upper respiratory tract of cats. Recent studies have shown that cells infected with FCV undergo apoptosis, as evidenced by caspase activation, chromatin condensation and cleavage of poly(ADP-ribose) polymerase. Here, the upstream events were investigated in order to define the molecular mechanism of apoptosis in FCV-infected cells. It was shown that FCV induced translocation of phosphatidylserine to the cell outer membrane and release of cytochrome c from mitochondria at about 6–8 h post-infection. These events were preceded by the loss of mitochondrial membrane potential and Bax translocation from the cytosol to mitochondria between 4 and 6 h after infection. Release of cytochrome c from mitochondria triggered the activation of caspase-9 and the subsequent activation of the executioner caspase, caspase-3. These results suggest that the mitochondrial pathway of apoptosis is triggered during FCV infection.
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Cavicchio, Lara, Andrea Laconi, Alessandra Piccirillo et Maria Serena Beato. « Swine Norovirus : Past, Present, and Future ». Viruses 14, no 3 (5 mars 2022) : 537. http://dx.doi.org/10.3390/v14030537.
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Norovirus, an ssRNA + virus of the family Caliciviridae, is a leading disease burden in humans worldwide, causing an estimated 600 million cases of acute gastroenteritis every year. Since the discovery of norovirus in the faeces of swine in Japan in the 1990s, swine norovirus has been reported in several countries on several continents. The identification of the human-associated GII.4 genotype in swine has raised questions about this animal species as a reservoir of norovirus with zoonotic potential, even if species-specific P-types are usually detected in swine. This review summarises the available data regarding the geographic distribution of norovirus in swine, the years of detection, the genotype characterisation, and the prevalence in specific production groups. Furthermore, we discuss the major bottlenecks for the detection and characterisation of swine noroviruses.
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Helle, Francois, Lynda Handala, Marine Bentz, Gilles Duverlie et Etienne Brochot. « Intercellular Transmission of Naked Viruses through Extracellular Vesicles : Focus on Polyomaviruses ». Viruses 12, no 10 (26 septembre 2020) : 1086. http://dx.doi.org/10.3390/v12101086.
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Extracellular vesicles have recently emerged as a novel mode of viral transmission exploited by naked viruses to exit host cells through a nonlytic pathway. Extracellular vesicles can allow multiple viral particles to collectively traffic in and out of cells, thus enhancing the viral fitness and diversifying the transmission routes while evading the immune system. This has been shown for several RNA viruses that belong to the Picornaviridae, Hepeviridae, Reoviridae, and Caliciviridae families; however, recent studies also demonstrated that the BK and JC viruses, two DNA viruses that belong to the Polyomaviridae family, use a similar strategy. In this review, we provide an update on recent advances in understanding the mechanisms used by naked viruses to hijack extracellular vesicles, and we discuss the implications for the biology of polyomaviruses.
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Stuart, Amanda D., et T. David K. Brown. « Entry of Feline Calicivirus Is Dependent on Clathrin-Mediated Endocytosis and Acidification in Endosomes ». Journal of Virology 80, no 15 (1 août 2006) : 7500–7509. http://dx.doi.org/10.1128/jvi.02452-05.
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ABSTRACT Feline calicivirus is a major causative agent of respiratory disease in cats. It is also one of the few cultivatable members of Caliciviridae. We have examined the entry process of feline calicivirus (FCV). An earlier study demonstrated that acidification in endosomes may be required. We have confirmed this observation and expanded upon it, demonstrating, using drugs to inhibit the various endocytic pathways and dominant-negative mutants, that FCV infects cells via clathrin-mediated endocytosis. We have also observed that FCV permeabilizes cell membranes early during infection to allow the coentry of toxins such as α-sarcin. Inhibitors of endosome acidification such as chloroquine and bafilomycin A1 blocked this permeabilization event, demonstrating that acidification is required for uncoating of the genome and access to the cytoplasm.
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Li, Zhaoming, Kaimin Song, Yongzhen Du, Zhuanglong Zhang, Rupeng Fan, Pimiao Zheng et Jianzhu Liu. « Diagnosis of a Rabbit Hemorrhagic Disease Virus 2 (RHDV2) and the Humoral Immune Protection Effect of VP60 Vaccine ». Current Issues in Molecular Biology 45, no 8 (8 août 2023) : 6605–17. http://dx.doi.org/10.3390/cimb45080417.
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Rabbit hemorrhagic disease (RHD) is known as rabbit plague and hemorrhagic pneumonia. It is an acute, septic, and highly fatal infectious disease caused by the Lagovirus rabbit hemorrhagic disease virus (RHDV) in the family Caliciviridae that infects wild and domestic rabbits and hares (lagomorphs). At present, RHDV2 has caused huge economic losses to the commercial rabbit trade and led to a decline in the number of wild lagomorphs worldwide. We performed a necropsy and pathological observations on five dead rabbits on a rabbit farm in Tai’an, China. The results were highly similar to the clinical and pathological changes of typical RHD. RHDV2 strain was isolated and identified by RT-PCR, and partial gene sequencing and genetic evolution analysis were carried out. There were significant differences in genetic characteristics and antigenicity between RHDV2 and classical RHDV strain, and the vaccine prepared with the RHDV strain cannot effectively prevent rabbit infection with RHDV2. Therefore, we evaluated the protective efficacy of a novel rabbit hemorrhagic virus baculovirus vector inactivated vaccine (VP60) in clinical application by animal regression experiment. The result showed that VP60 could effectively induce humoral immunity in rabbits. The vaccine itself had no significant effect on the health status of rabbits. This study suggested that the clinical application of VP60 may provide new ideas for preventing the spread of RHD2.
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Katpally, Umesh, Christiane E. Wobus, Kelly Dryden, Herbert W. Virgin et Thomas J. Smith. « Structure of Antibody-Neutralized Murine Norovirus and Unexpected Differences from Viruslike Particles ». Journal of Virology 82, no 5 (19 décembre 2007) : 2079–88. http://dx.doi.org/10.1128/jvi.02200-07.
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ABSTRACT Noroviruses (family Caliciviridae) are the major cause of epidemic nonbacterial gastroenteritis in humans, but the mechanism of antibody neutralization is unknown and no structure of an infectious virion has been reported. Murine norovirus (MNV) is the only norovirus that can be grown in tissue culture, studied in an animal model, and reverse engineered via an infectious clone and to which neutralizing antibodies have been isolated. Presented here are the cryoelectron microscopy structures of an MNV virion and the virion in complex with neutralizing Fab fragments. The most striking differences between MNV and previous calicivirus structures are that the protruding domain is lifted off the shell domain by ∼16Å and rotated ∼40° in a clockwise fashion and forms new interactions at the P1 base that create a cagelike structure engulfing the shell domains. Neutralizing Fab fragments cover the outer surface of each copy of the capsid protein P2 domains without causing any apparent conformational changes. These unique features of MNV suggest that at least some caliciviruses undergo a capsid maturation process akin to that observed with other plant and bacterial viruses.
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CANDIDO, M., A. L. F. ALENCAR, S. R. ALMEIDA-QUEIROZ, M. G. BUZINARO, F. S. MUNIN, S. H. S. GODOY, M. C. LIVONESI, A. M. FERNANDES et R. L. M. SOUSA. « First detection and molecular characterization ofNebovirusin Brazil ». Epidemiology and Infection 144, no 9 (22 janvier 2016) : 1876–78. http://dx.doi.org/10.1017/s0950268816000029.
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SUMMARYNebovirusis a new genus of viruses belonging to the Caliciviridae family recently characterized in cattle, and is associated with gastrointestinal disorders, such as diarrhoea, anorexia and intestinal lesions particularly in calves. The aim of this study was to investigate the prevalence of neboviruses in Brazilian cattle and analyse phylogenetically the virus strains detected. A prevalence of 4·8% of neboviruses in faecal samples from 62 head of cattle from different Brazilian states was detected. All positive animals were aged <20 days and had diarrhoea. Phylogenetic analysis clustered the virus sequences into the Newbury1 clade. There was >96·0% nt (100% aa) sequence identity between the virus sequences in this study and >88·8% nt (>94·4% aa) identity with Newbury1/UK. Our results indicate, for the first time, the occurrence of neboviruses in Brazil as well as in South America, and the first Newbury1-like nebovirus found outside the UK.
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Mikalsen, Aase B., Pål Nilsen, Marianne Frøystad-Saugen, Karine Lindmo, Trygve M. Eliassen, Marit Rode et Øystein Evensen. « Characterization of a Novel Calicivirus Causing Systemic Infection in Atlantic Salmon (Salmo salar L.) : Proposal for a New Genus of Caliciviridae ». PLoS ONE 9, no 9 (9 septembre 2014) : e107132. http://dx.doi.org/10.1371/journal.pone.0107132.
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Matsumoto, Naomi, Shiho Kurokawa, Shigeyuki Tamiya, Yutaka Nakamura, Naomi Sakon, Shoko Okitsu, Hiroshi Ushijima, Yoshikazu Yuki, Hiroshi Kiyono et Shintaro Sato. « Replication of Human Sapovirus in Human-Induced Pluripotent Stem Cell-Derived Intestinal Epithelial Cells ». Viruses 15, no 9 (15 septembre 2023) : 1929. http://dx.doi.org/10.3390/v15091929.
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Sapoviruses, like noroviruses, are single-stranded positive-sense RNA viruses classified in the family Caliciviridae and are recognized as a causative pathogen of diarrhea in infants and the elderly. Like human norovirus, human sapovirus (HuSaV) has long been difficult to replicate in vitro. Recently, it has been reported that HuSaV can be replicated in vitro by using intestinal epithelial cells (IECs) derived from human tissues and cell lines derived from testicular and duodenal cancers. In this study, we report that multiple genotypes of HuSaV can sufficiently infect and replicate in human-induced pluripotent stem cell-derived IECs. We also show that this HuSaV replication system can be used to investigate the conditions for inactivation of HuSaV by heat and alcohol, and the effects of virus neutralization of antisera obtained by immunization with vaccine antigens, under conditions closer to the living environment. The results of this study confirm that HuSaV can also infect and replicate in human normal IECs regardless of their origin and are expected to contribute to future virological studies.
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Lyashchuk, Yulia Olegovna, Alexey Yurievich Ovchinnikov et Yulia Borisovna Kostrova. « Structural analysis of alimentary-caused morbidity of the population caused by biological risk factors significant in the production and processing of food products ». Agrarian Scientific Journal, no 6 (26 juin 2023) : 75–82. http://dx.doi.org/10.28983/asj.y2023i6pp75-82.
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The article presents an analysis of the ten-year dynamics of alimentary-related morbidity in the population of the Ryazan region, caused by biological risk factors that are significant in the production and processing of food products. The most significant groups of biological risk factors requiring special sanitary control have been identified. In the course of the research, statistical methods were used to analyze and evaluate cyclical trends in morbidity, methods for predicting the dynamics of morbidity, comparing the dynamics of infectious and parasitic morbidity with the dynamics of alimentary-related biological risk factors. The results of the analysis over a ten-year period showed that the greatest danger at present in terms of food safety is posed by risk factors of bacterial etiology. These are bacteria of the genus Salmonella (Lignieres 1900), diarrheagenic serovariants of Escherichia coli (Migula 1895, Castellani and Chalmers 1919) and viral etiology: Norwalk virus (genus Norovirus, family Caliciviridae, International Committee on Virus Taxonomy, 2002) and rotaviruses (Rotavirus, family Reoviridae, International Committee on Virus Taxonomy, 1978). The work is of practical importance for further assessment of the level of biological risk of alimentary-related factors in terms of epidemiological indicators of infectious and parasitic morbidity.
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Álvarez, Ángel L., Aroa Arboleya, Fábio A. Abade dos Santos, Alberto García-Manso, Inés Nicieza, Kevin P. Dalton, Francisco Parra et José M. Martín-Alonso. « Highs and Lows in Calicivirus Reverse Genetics ». Viruses 16, no 6 (28 mai 2024) : 866. http://dx.doi.org/10.3390/v16060866.
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In virology, the term reverse genetics refers to a set of methodologies in which changes are introduced into the viral genome and their effects on the generation of infectious viral progeny and their phenotypic features are assessed. Reverse genetics emerged thanks to advances in recombinant DNA technology, which made the isolation, cloning, and modification of genes through mutagenesis possible. Most virus reverse genetics studies depend on our capacity to rescue an infectious wild-type virus progeny from cell cultures transfected with an “infectious clone”. This infectious clone generally consists of a circular DNA plasmid containing a functional copy of the full-length viral genome, under the control of an appropriate polymerase promoter. For most DNA viruses, reverse genetics systems are very straightforward since DNA virus genomes are relatively easy to handle and modify and are also (with few notable exceptions) infectious per se. This is not true for RNA viruses, whose genomes need to be reverse-transcribed into cDNA before any modification can be performed. Establishing reverse genetics systems for members of the Caliciviridae has proven exceptionally challenging due to the low number of members of this family that propagate in cell culture. Despite the early successful rescue of calicivirus from a genome-length cDNA more than two decades ago, reverse genetics methods are not routine procedures that can be easily extrapolated to other members of the family. Reports of calicivirus reverse genetics systems have been few and far between. In this review, we discuss the main pitfalls, failures, and delays behind the generation of several successful calicivirus infectious clones.
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Liu, Guangqing, Zheng Ni, Tao Yun, Bin Yu, Liu Chen, Wei Zhao, Jionggang Hua et Jianping Chen. « A DNA-launched reverse genetics system for rabbit hemorrhagic disease virus reveals that the VP2 protein is not essential for virus infectivity ». Journal of General Virology 89, no 12 (1 décembre 2008) : 3080–85. http://dx.doi.org/10.1099/vir.0.2008/003525-0.
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Rabbit hemorrhagic disease virus (RHDV), a member of the family Caliciviridae comprising positive-stranded RNA viruses, is a highly virulent pathogen of rabbits. Until recently, studies into the molecular mechanisms of RHDV replication and pathogenesis have been hindered by the lack of an in vitro culture system and reverse genetics. This study describes the generation of a DNA-based reverse genetics system for RHDV and the subsequent investigation of the biological role of the RHDV VP2 protein. The full-length RHDV genome was assembled as a single cDNA clone and placed under the control of the eukaryotic human cytomegalovirus promoter. Transfection of cells with the DNA clone resulted in a clear cytopathic effect and the generation of infectious progeny virions. The reconstituted virus was stable and grew to titres similar to that of the parental virus. Although previous reports have suggested that the minor structural protein (VP2) of other caliciviruses is essential for the production of infectious virions, using the DNA-launch-based RHDV reverse genetics system described here it was demonstrated that VP2 is not essential for RHDV infectivity. Transfection of cells with a cDNA clone of RHDV lacking VP2 resulted in the generation of infectious virions. These studies indicate that the presence of VP2 could reduce the replication of RHDV, suggesting that it may play a regulatory role in the life cycle of RHDV.
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Navarro, Gemma, Rosa M. Sala, Ferran Segura, César Arias, Pilar Varela, Pilar Peña, Teresa Llovet et al. « An Outbreak of Norovirus Infection in a Long-Term-Care Unit in Spain ». Infection Control & ; Hospital Epidemiology 26, no 3 (mars 2005) : 259–62. http://dx.doi.org/10.1086/502536.
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AbstractBackground:Norovirus belongs to the Caliciviridae family and causes outbreaks of infectious enteritis by fecal-oral transmission. In Spain, there have been few outbreaks reported due to this virus. We describe an outbreak on a long-term-care hospital ward.Methods:Cases were classified as probable, confirmed, and secondary. Stool cultures were performed. Polymerase chain reaction detection of norovirus was also performed.Results:The outbreak occurred from December 7 to 28, 2001, involving 60 cases (32 patients, 19 staff members, 8 patients' relatives, and 1 relative of a staff member). Most (82%) of the cases were female. The most frequently involved ages were 20 to 39 years for staff members and 70 to 89 years for patients. The incubation period of secondary cases in patients' families had a median of 48 hours (range, 1 to 7 days). Clinical symptoms included diarrhea (85%), vomiting (75%), fever (37%), nausea (23%), and abdominal pain (12%). Median duration of the disease was 48 hours (range, 1 to 7 days). All cases resolved and the outbreak halted with additional hygienic measures. Stool cultures were all negative for enteropathogenic bacteria and rotaviruses. In 16 of 23 cases, the norovirus genotype 2 antigen was detected.Conclusion:This outbreak of gastroenteritis due to norovirus genotype 2 affected patients, staff members, and their relatives in a long-term-care facility and was controlled in 21 days.
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Liu, Jia, Xiyan Li, Wentao Song, Xiaoxu Zeng, Hui Li, Lei Yang et Dayan Wang. « The Multi-Kingdom Microbiome of Wintering Migratory Birds in Poyang Lake, China ». Viruses 16, no 3 (3 mars 2024) : 396. http://dx.doi.org/10.3390/v16030396.
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Wild birds are a natural reservoir for zoonotic viruses. To clarify the role of migratory birds in viruses spread in Poyang Lake, we investigated the microbiome of 250 wild bird samples from 19 species in seven orders. The bacterial and viral content abundance and diversity were preliminarily evaluated by Kraken2 and Bracken. After de novo assembly by Megahit and Vamb, viral contigs were identified by CheckV. The reads remapped to viral contigs were quantified using Bowtie2. The bacterial microbiome composition of the samples covers 1526 genera belonging to 175 bacterial orders, while the composition of viruses covers 214 species belonging to 22 viral families. Several taxonomic biomarkers associated with avian carnivory, oral sampling, and raptor migration were identified. Additionally, 17 complete viral genomes belonging to Astroviridae, Caliciviridae, Dicistroviridae, Picornaviridae, and Tombusviridae were characterized, and their phylogenetic relationships were analyzed. This pioneering metagenomic study of migratory birds in Poyang Lake, China illuminates the diverse microbial landscape within these birds. It identifies potential pathogens, and uncovers taxonomic biomarkers relevant to varied bird habitats, feeding habits, ecological classifications, and sample types, underscoring the public health risks associated with wintering migratory birds.
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Sano, Daisuke, Takatomo Ohta, Arata Nakamura, Toyoko Nakagomi, Osamu Nakagomi et Satoshi Okabe. « Culture-Independent Evaluation of Nonenveloped-Virus Infectivity Reduced by Free-Chlorine Disinfection ». Applied and Environmental Microbiology 81, no 8 (13 février 2015) : 2819–26. http://dx.doi.org/10.1128/aem.03802-14.
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ABSTRACTThe inability of molecular detection methods to distinguish disinfected virions from infectious ones has hampered the assessment of infectivity for enteric viruses caused by disinfection practices. In the present study, the reduction of infectivity of murine norovirus S7-PP3 and mengovirus vMC0, surrogates of human noroviruses and enteroviruses, respectively, caused by free-chlorine treatment was characterized culture independently by detecting carbonyl groups on viral capsid protein. The amount of carbonyls on viral capsid protein was evaluated by the proportion of biotinylated virions trapped by avidin-immobilized gel (percent adsorbed). This culture-independent approach demonstrated that the percent adsorbed was significantly correlated with the logarithm of the infectious titer of tested viruses. Taken together with the results of previous reports, the result obtained in this study indicates that the amount of carbonyls on viral capsid protein of four important families of waterborne pathogenic viruses,Astroviridae,Reoviridae,Caliciviridae, andPicornaviridae, is increased in proportion to the received oxidative stress of free chlorine. There was also a significant correlation between the percent adsorbed and the logarithm of the ratio of genome copy number to PFU, which enables estimation of the infectious titer of a subject virus by measuring values of the total genome copy number and the percent adsorbed. The proposed method is applicable when the validation of a 4-log reduction of viruses, a requirement in U.S. EPA guidelines for virus removal from water, is needed along with clear evidence of the oxidation of virus particles with chlorine-based disinfectants.
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A. Duarte, Matheus, João M. F. Silva, Clara R. Brito, Danilo S. Teixeira, Fernando L. Melo, Bergmann M. Ribeiro, Tatsuya Nagata et Fabrício S. Campos. « Faecal Virome Analysis of Wild Animals from Brazil ». Viruses 11, no 9 (30 août 2019) : 803. http://dx.doi.org/10.3390/v11090803.
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The Brazilian Cerrado fauna shows very wide diversity and can be a potential viral reservoir. Therefore, the animal’s susceptibility to some virus can serve as early warning signs of potential human virus diseases. Moreover, the wild animal virome of this biome is unknown. Based on this scenario, high-throughput sequencing contributes a robust tool for the identification of known and unknown virus species in this environment. In the present study, faeces samples from cerrado birds (Psittacara leucophthalmus, Amazona aestiva, and Sicalis flaveola) and mammals (Didelphis albiventris, Sapajus libidinosus, and Galictis cuja) were collected at the Veterinary Hospital, University of Brasília. Viral nucleic acid was extracted, submitted to random amplification, and sequenced by Illumina HiSeq platform. The reads were de novo assembled, and the identities of the contigs were evaluated by Blastn and tblastx searches. Most viral contigs analyzed were closely related to bacteriophages. Novel archaeal viruses of the Smacoviridae family were detected. Moreover, sequences of members of Adenoviridae, Anelloviridae, Circoviridae, Caliciviridae, and Parvoviridae families were identified. Complete and nearly complete genomes of known anelloviruses, circoviruses, and parvoviruses were obtained, as well as putative novel species. We demonstrate that the metagenomics approach applied in this work was effective for identification of known and putative new viruses in faeces samples from Brazilian Cerrado fauna.
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Mathew, Lolita George, Melissa M. Herbst-Kralovetz et Hugh S. Mason. « Norovirus Narita 104 Virus-Like Particles Expressed inNicotiana benthamianaInduce Serum and Mucosal Immune Responses ». BioMed Research International 2014 (2014) : 1–9. http://dx.doi.org/10.1155/2014/807539.
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Narita 104 virus is a human pathogen belonging to the norovirus (family Caliciviridae) genogroup II. Noroviruses cause epidemic gastroenteritis worldwide. To explore the potential of developing a plant-based vaccine, a plant optimized gene encoding Narita 104 virus capsid protein (NaVCP) was expressed transiently inNicotiana benthamianausing a tobacco mosaic virus expression system. NaVCP accumulated up to approximately 0.3 mg/g fresh weight of leaf at 4 days postinfection. Initiation of hypersensitive response-like symptoms followed by tissue necrosis necessitated a brief infection time and was a significant factor limiting expression. Transmission electron microscopy of plant-derived NaVCP confirmed the presence of fully assembled virus-like particles (VLPs). In this study, an optimized method to express and partially purify NaVCP is described. Further, partially purified NaVCP was used to immunize mice by intranasal delivery and generated significant mucosal and serum antibody responses. Thus, plant-derived Narita 104 VLPs have potential for use as a candidate subunit vaccine or as a component of a multivalent subunit vaccine, along with other genotype-specific plant-derived VLPs.