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Houssam Attoui - One of the best experts on this subject based on the ideXlab platform.

  • eLS - Coltiviruses and Seadornaviruses
    eLS, 2015
    Co-Authors: Fauziah Mohd Jaafar, Peter P.c. Mertens, Houssam Attoui
    Abstract:

    Coltiviruses and seadornaviruses are members of the family Reoviridae, which encompasses alongside the genera Coltivirus and Seadornavirus, 13 other genera of viruses that can infect mammals, birds, aquatic animals, reptiles, insects, plants, fungi and protists. Coltiviruses are transmitted by hard ticks of the family Ixodidae, whereas seadornaviruses are mosquito-borne. These viruses can infect humans, following the bite of adult infected female ticks or mosquitoes, causing febrile illnesses and are occasionally responsible for encephalitis. Coltiviruses are principally endemic in the north-western parts of the United States and Canada and were also reported in European countries, including France and Germany. Antibodies to Coltiviruses have also been identified from patients in the former Czechoslovakia and South Korea. Seadornaviruses are principally endemic in the south-east Asia, although recent data showed that there has been an expansion of their distribution northwards, reaching the north-western Chinese borders. Banna virus (Seadornavirus) has been isolated from human encephalitis cases. Key Concepts Coltiviruses are transmitted by adult female tick (family Ixodidae) bite and have animal reservoirs. Coltiviruses can infect humans causing febrile illnesses and can cause encephalitis in rare cases. Seadornaviruses are transmitted by mosquitoes and no animal reservoir is known to date. Seadornaviruses can infect animals and humans causing febrile illnesses and were reported to be responsible for cases of encephalitis. Coltiviruses show an evolutionary relationship to the turreted mycoreoviruses, aquareoviruses and orthoreoviruses. Seadornaviruses show an evolutionary relationship to the nonturreted rotaviruses. Coltiviruses seem to represent a missing link between turreted and nonturreted members of the family Reoviridae. Differential diagnostic serological and molecular assays for Coltiviruses and seadornaviruses are available. Structure of the viral particles of Banna virus shows striking similarities to that of the rotaviruses. Keywords: Coltivirus; seadornavirus; Reoviridae; encephalitis; vector-borne virus

  • SEROLOGIC AND MOLECULAR DIAGNOSIS OF COLORADO TICK FEVER VIRAL INFECTIONS
    2015
    Co-Authors: Houssam Attoui, Frederique Billoir, Jean-marie Bruey, Philippe De Micco, De Lamballerie
    Abstract:

    Abstract. Molecular and serologic methods usable for the biological diagnosis of Coltivirus infection are reported. We designed a multiplex reverse transcription–polymerase chain reaction system that allowed the simultaneous and specific amplification of three genomic segments from as little as 0.01 plaque-forming units. Another system in the S2 viral segment permitted the differential diagnosis of American and European viral isolates. We also discuss some improvements of previous ELISAs, and the results obtained with paired sera from Colorado tick fever (CTF) virus– infected individuals. Western blot analysis was developed that allowed the detection of antibodies to a 38-kD viral protein in all tested sera. It also enabled the detection of anti-CTF virus antibodies in ELISA-negative sera. Specific IgM antibodies against a synthetic viral peptide could be detected in sera at the acute stage of the infection. Together, these results should permit the diagnosis of Coltivirus infection at any stage of the pathology. Colorado tick fever (CTF) is a severe tick-borne disease that is usually self-limited. This disease occurs in 11 western states in the United States and has also been reported in Canada.1 Yearly, 200–400 cases are reported throughout the endemic states in the United States.1,2 The clinical manifes-tations appear following the bite of the infected adult Rock

  • Complete characterisation of the American grass carp reovirus genome (genus Aquareovirus: family Reoviridae) reveals an evolutionary link between aquareoviruses and Coltiviruses.
    Virology, 2008
    Co-Authors: Fauziah Mohd Jaafar, Philippe De Micco, Philippe Biagini, Jean-françois Cantaloube, Peter P.c. Mertens, Andrew E. Goodwin, Mourad Belhouchet, Gwenn E. Merry, Qin Fang, Houssam Attoui
    Abstract:

    An aquareovirus was isolated from several fish species in the USA (including healthy golden shiners) that is not closely related to members of species Aquareovirus A, B and C. The virus, which is atypical (does not cause syncytia in cell cultures at neutral pH), was implicated in a winter die-off of grass carp fingerlings and has therefore been called 'American grass carp reovirus' (AGCRV). Complete nucleotide sequence analysis of the AGCRV genome and comparisons to the other aquareoviruses showed that it is closely related to golden ide reovirus (GIRV) (>92% amino acid [aa] identity in VP5(NTPase) and VP2(Pol)). However, comparisons with grass carp reovirus (Aquareovirus C) and chum salmon reovirus (Aquareovirus A) showed only 22% to 76% aa identity in different viral proteins. These findings have formed the basis for the recognition of AGCRV and GIRV as members of a new Aquareovirus species 'Aquareovirus G' by ICTV. Further sequence comparisons to other members of the family Reoviridae suggest that there has been an 'evolutionary jump,' involving a change in the number of genome segments, between the aquareoviruses (11 segments) and Coltiviruses (12 segments). Segment 7 of AGRCV encodes two proteins, from two distinct ORFs, which are homologues of two Coltivirus proteins encoded by genome segments 9 and 12. A similar model has previously been reported for the rotaviruses and seadornaviruses.

  • Coltiviruses and seadornaviruses in North America, Europe, and Asia.
    Emerging Infectious Diseases, 2005
    Co-Authors: Houssam Attoui, Philippe De Micco, Fauziah Mohd Jaafar, X. De Lamballerie
    Abstract:

    Coltiviruses are tickborne viruses of the genus Coltivirus. The type species, Colorado tick fever virus (from North America), has been isolated from patients with flulike syndromes, meningitis, encephalitis, and other severe complications. Another Coltivirus, Eyach virus, has been isolated from ticks in France and Germany and incriminated in febrile illnesses and neurologic syndromes. Seadornaviruses are endemic in Southeast Asia, particularly Indonesia and China. The prototype virus of the genus, Banna virus (BAV), has been isolated from many mosquito species, humans with encephalitis, pigs, and cattle. Two other seadornaviruses, Kadipiro and Liao Ning, were isolated only from mosquitoes. The epidemiology of seadornaviruses remains poorly documented. Evidence suggests that BAV is responsible for encephalitis in humans. Infection with BAV may be underreported because it circulates in regions with a high incidence of Japanese encephalitis and could be misdiagnosed as this disease.

  • Tick-borne virus diseases of human interest in Europe.
    Clinical microbiology and infection : the official publication of the European Society of Clinical Microbiology and Infectious Diseases, 2004
    Co-Authors: Rémi N. Charrel, Houssam Attoui, J.c. Clegg, Vincent Deubel, T.v. Frolova, Ernest A. Gould, T.s. Gritsun, Franz X. Heinz, Milan Labuda
    Abstract:

    Several human diseases in Europe are caused by viruses transmitted by tick bite. These viruses belong to the genus Flavivirus, and include tick-borne encephalitis virus, Omsk haemorrhagic fever virus, louping ill virus, Powassan virus, Nairovirus (Crimean-Congo haemorrhagic fever virus) and Coltivirus (Eyach virus). All of these viruses cause more or less severe neurological diseases, and some are also responsible for haemorrhagic fever. The epidemiology, clinical picture and methods for diagnosis are detailed in this review. Most of these viral pathogens are classified as Biosafety Level 3 or 4 agents, and therefore some of them have been classified in Categories A–C of potential bioterrorism agents by the Centers for Disease Control and Prevention. Their ability to cause severe disease in man means that these viruses, as well as any clinical samples suspected of containing them, must be handled with specific and stringent precautions.

X. De Lamballerie - One of the best experts on this subject based on the ideXlab platform.

  • Coltiviruses and seadornaviruses in North America, Europe, and Asia.
    Emerging Infectious Diseases, 2005
    Co-Authors: Houssam Attoui, Philippe De Micco, Fauziah Mohd Jaafar, X. De Lamballerie
    Abstract:

    Coltiviruses are tickborne viruses of the genus Coltivirus. The type species, Colorado tick fever virus (from North America), has been isolated from patients with flulike syndromes, meningitis, encephalitis, and other severe complications. Another Coltivirus, Eyach virus, has been isolated from ticks in France and Germany and incriminated in febrile illnesses and neurologic syndromes. Seadornaviruses are endemic in Southeast Asia, particularly Indonesia and China. The prototype virus of the genus, Banna virus (BAV), has been isolated from many mosquito species, humans with encephalitis, pigs, and cattle. Two other seadornaviruses, Kadipiro and Liao Ning, were isolated only from mosquitoes. The epidemiology of seadornaviruses remains poorly documented. Evidence suggests that BAV is responsible for encephalitis in humans. Infection with BAV may be underreported because it circulates in regions with a high incidence of Japanese encephalitis and could be misdiagnosed as this disease.

  • Recombinant VP6-based enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies to Eyach virus (genus Coltivirus)
    Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology, 2004
    Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, X. De Lamballerie
    Abstract:

    Background: Eyach virus (EYAV) is a tick-borne virus belonging to genus Coltivirus, family Reoviridae. It was isolated in Germany and France and has been suspected to be responsible for neurological diseases in humans. To date, there has been no relatively rapid and relatively specific serological assay for EYAV. Objectives: To develop an ELISA for EYAV, suitable for epidemiological and/or diagnostic purposes. This ELISA should allow to distinguish between infections with EYAV and the related Colorado tick fever virus (CTFV). Study Design: VP6, VP7 and VP12 of Eyach virus (the three proteins most divergent between EYAV and CTFV) were expressed in bacteria using the pGEX-4T-2 vector. A partial sequence of VP6 (designated pVP6) was chosen to develop an ELISA for detecting anti-EYAV IgG antibodies in serum. This choice was based on two observations: (i) the homologous VP7 protein of CTFV was successfully used as a target for detecting antibodies to CTFV (the VP7 showed the highest reactivity to an anti-CTFV antibody among all CTFV expressed proteins); (ii) to distinguish infection with EYAV from a CTFV infection: the expressed sequence was chosen within a region which is highly divergent (49% of amino acid identity) from the homologous VP7 sequence of CTFV. Results and conclusions: pVP6 was shown to be the most reactive among the three expressed proteins. The elaborated pVP6 ELISA was evaluated with 340 sera of French blood donors, and found to exhibit a specificity of 100% (no false positives). Furthermore, no cross reaction was detected with antibody to CTFV, thus permitting us to distinguish between infections by either virus. The use of this recombinant protein for serological assays is a good alternative to the use of native EYAV antigen due to the extremely low productivity of the virus in cell culture, and the requirement for suckling mice. This ELISA will be useful to clarify the epidemiological status and the suspected pathogenicity of the virus.

  • Recombinant VP7-Based Enzyme-Linked Immunosorbent Assay for Detection of Immunoglobulin G Antibodies to Colorado Tick Fever Virus
    Journal of Clinical Microbiology, 2003
    Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Pierre Gallian, Philippe Biagini, Jean-françois Cantaloube, X. De Lamballerie
    Abstract:

    VP6, VP7, VP9, VP10, VP11, and VP12 of Colorado tick fever virus (CTF virus), a virus member of the genus Coltivirus, family Reoviridae, were expressed in bacteria with the pGEX-4T-2 vector. A partial sequence of VP7 (designated pVP7) was chosen to elaborate an enzyme-linked immunosorbent assay (ELISA) for detecting anti-CTF virus immunoglobulin G (IgG) antibodies in humans. This was based on two observations: (i) among all expressed proteins, pVP7 showed the highest immunoreactivity to an anti-CTF virus hyperimmune ascitic fluid; (ii) to provide the highest selectivity of antibody detection, the expressed sequence was chosen within a region which is highly divergent (49% amino acid identity) from the homologous sequence of another Coltivirus, the Eyach virus. The pVP7 ELISA was evaluated with 368 serum samples from French blood donors and found to provide 98.1% specificity. Assays with the Calisher set of human serum samples, positive for anti-CTF virus antibodies (C. H. Calisher, J. D. Poland, S. B. Calisher, and L. A Warmoth, J. Clin. Microbiol. 22:84-88, 1985), showed that the pVP7 ELISA provided 100% sensitivity for the tested population. After elaboration of recombinant-protein-based ELISAs for diagnosis of infections with members of the viral genera Orbivirus, Orthoreovirus, and Rotavirus, it was shown that a recombinant protein could be used to detect antibodies to the human pathogen Colorado tick fever virus.

  • Genus Coltivirus (family Reoviridae): genomic and morphologic characterization of Old World and New World viruses
    Archives of Virology, 2002
    Co-Authors: Houssam Attoui, Jean-françois Cantaloube, P. De Micco, F. Mohd Jaafar, P. Biagini, F. A. Murphy, X. De Lamballerie
    Abstract:

     We report a genomic and morphologic study of the European Eyach (EYA) virus (genus Coltivirus , family Reoviridae ) and a comparative analysis with the American Colorado tick fever (CTF) virus (the type species of the genus). The previously established, but distant, antigenic relationship between these viruses was strengthened by genetic findings (presence of cognate genes, amino acid identity between 55 and 88%, similar conserved terminal motifs, suspected read-through phenomenon in segment 9 of both viruses) and by indistinguishable ultramicroscopic morphologies. Moreover, putative constitutive modifying enzyme activities were suspected to be carried out by homologous viral proteins (RNA-dependent RNA polymerase, methyl/guanylyl transferase, NTPase). These findings, together with the comparative analysis to genomes of south-east Asian isolates, support the recent classification of arboviruses with 12 segments of dsRNA within two distinct genera (genus Coltivirus and genus Seadornavirus ) and raise interesting questions about the evolutionary origins of Coltiviruses. The previously proposed hypothesis that EYA virus was derived from an ancestral virus introduced in Europe with the migration of lagomorphs from North-America, would imply a divergence date between American and European isolates of over 50 million years ago (MYA). This analysis allows for the first time to propose an evolutionary rate for virus dsRNA genomes which was found to be in the order of 10^−8 to 10^−9 mutations/nt/year, a rate similar to that of dsDNA genomes.

  • Genus Coltivirus (family Reoviridae): genomic and morphologic characterization of Old World and New World viruses.
    Archives of Virology, 2002
    Co-Authors: Houssam Attoui, Philippe Biagini, Jean-françois Cantaloube, P. De Micco, F. A. Murphy, F. Mohd Jaafar, X. De Lamballerie
    Abstract:

    We report a genomic and morphologic study of the European Eyach (EYA) virus (genus Coltivirus, family Reoviridae) and a comparative analysis with the American Colorado tick fever (CTF) virus (the type species of the genus). The previously established, but distant, antigenic relationship between these viruses was strengthened by genetic findings (presence of cognate genes, amino acid identity between 55 and 88%, similar conserved terminal motifs, suspected read-through phenomenon in segment 9 of both viruses) and by indistinguishable ultramicroscopic morphologies. Moreover, putative constitutive modifying enzyme activities were suspected to be carried out by homologous viral proteins (RNA-dependent RNA polymerase, methyl/guanylyl transferase, NTPase).

Fabian H. Leendertz - One of the best experts on this subject based on the ideXlab platform.

  • A novel Coltivirus-related virus isolated from free-tailed bats from Côte d’Ivoire is able to infect human cells in vitro
    Virology Journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Background Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. Methods As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. Results We isolated and characterised a novel reovirus from blood of free-tailed bats ( Chaereophon aloysiisabaudiae ) captured in 2006 in Côte d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. Conclusion The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

  • A novel Coltivirus-related virus isolated from free-tailed bats from Côte d’Ivoire is able to infect human cells in vitro
    Virology journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. We isolated and characterised a novel reovirus from blood of free-tailed bats (Chaereophon aloysiisabaudiae) captured in 2006 in Cote d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

  • a novel Coltivirus related virus isolated from free tailed bats from cote d ivoire is able to infect human cells in vitro
    Virology Journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. We isolated and characterised a novel reovirus from blood of free-tailed bats (Chaereophon aloysiisabaudiae) captured in 2006 in Cote d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

Sabrina Weiss - One of the best experts on this subject based on the ideXlab platform.

  • A novel Coltivirus-related virus isolated from free-tailed bats from Côte d’Ivoire is able to infect human cells in vitro
    Virology Journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Background Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. Methods As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. Results We isolated and characterised a novel reovirus from blood of free-tailed bats ( Chaereophon aloysiisabaudiae ) captured in 2006 in Côte d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. Conclusion The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

  • A novel Coltivirus-related virus isolated from free-tailed bats from Côte d’Ivoire is able to infect human cells in vitro
    Virology journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. We isolated and characterised a novel reovirus from blood of free-tailed bats (Chaereophon aloysiisabaudiae) captured in 2006 in Cote d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

  • a novel Coltivirus related virus isolated from free tailed bats from cote d ivoire is able to infect human cells in vitro
    Virology Journal, 2017
    Co-Authors: Sabrina Weiss, Piotr Wojtek Dabrowski, Andreas Kurth, Siv Aina J. Leendertz, Fabian H. Leendertz
    Abstract:

    Zoonotic transmission events play a major role in the emergence of novel diseases. While such events are virtually impossible to predict, wildlife screening for potential emerging pathogens can be a first step. Driven by recent disease epidemics like severe acute respiratory syndrome (SARS), Middle East respiratory syndrome (MERS), and Ebola, bats have gained special interest as reservoirs of emerging viruses. As part of a bigger study investigating pathogens in African bats we screened animals for the presence of known and unknown viruses. We isolated and characterised a novel reovirus from blood of free-tailed bats (Chaereophon aloysiisabaudiae) captured in 2006 in Cote d’Ivoire. The virus showed closest relationship with two human pathogenic viruses, Colorado tick fever virus and Eyach virus, and was able to infect various human cell lines in vitro. The study shows the presence of a Coltivirus-related virus in bats from Sub-Sahara Africa. Serological studies could help to assess its impact on humans or wildlife health.

Philippe De Micco - One of the best experts on this subject based on the ideXlab platform.

  • SEROLOGIC AND MOLECULAR DIAGNOSIS OF COLORADO TICK FEVER VIRAL INFECTIONS
    2015
    Co-Authors: Houssam Attoui, Frederique Billoir, Jean-marie Bruey, Philippe De Micco, De Lamballerie
    Abstract:

    Abstract. Molecular and serologic methods usable for the biological diagnosis of Coltivirus infection are reported. We designed a multiplex reverse transcription–polymerase chain reaction system that allowed the simultaneous and specific amplification of three genomic segments from as little as 0.01 plaque-forming units. Another system in the S2 viral segment permitted the differential diagnosis of American and European viral isolates. We also discuss some improvements of previous ELISAs, and the results obtained with paired sera from Colorado tick fever (CTF) virus– infected individuals. Western blot analysis was developed that allowed the detection of antibodies to a 38-kD viral protein in all tested sera. It also enabled the detection of anti-CTF virus antibodies in ELISA-negative sera. Specific IgM antibodies against a synthetic viral peptide could be detected in sera at the acute stage of the infection. Together, these results should permit the diagnosis of Coltivirus infection at any stage of the pathology. Colorado tick fever (CTF) is a severe tick-borne disease that is usually self-limited. This disease occurs in 11 western states in the United States and has also been reported in Canada.1 Yearly, 200–400 cases are reported throughout the endemic states in the United States.1,2 The clinical manifes-tations appear following the bite of the infected adult Rock

  • Complete characterisation of the American grass carp reovirus genome (genus Aquareovirus: family Reoviridae) reveals an evolutionary link between aquareoviruses and Coltiviruses.
    Virology, 2008
    Co-Authors: Fauziah Mohd Jaafar, Philippe De Micco, Philippe Biagini, Jean-françois Cantaloube, Peter P.c. Mertens, Andrew E. Goodwin, Mourad Belhouchet, Gwenn E. Merry, Qin Fang, Houssam Attoui
    Abstract:

    An aquareovirus was isolated from several fish species in the USA (including healthy golden shiners) that is not closely related to members of species Aquareovirus A, B and C. The virus, which is atypical (does not cause syncytia in cell cultures at neutral pH), was implicated in a winter die-off of grass carp fingerlings and has therefore been called 'American grass carp reovirus' (AGCRV). Complete nucleotide sequence analysis of the AGCRV genome and comparisons to the other aquareoviruses showed that it is closely related to golden ide reovirus (GIRV) (>92% amino acid [aa] identity in VP5(NTPase) and VP2(Pol)). However, comparisons with grass carp reovirus (Aquareovirus C) and chum salmon reovirus (Aquareovirus A) showed only 22% to 76% aa identity in different viral proteins. These findings have formed the basis for the recognition of AGCRV and GIRV as members of a new Aquareovirus species 'Aquareovirus G' by ICTV. Further sequence comparisons to other members of the family Reoviridae suggest that there has been an 'evolutionary jump,' involving a change in the number of genome segments, between the aquareoviruses (11 segments) and Coltiviruses (12 segments). Segment 7 of AGRCV encodes two proteins, from two distinct ORFs, which are homologues of two Coltivirus proteins encoded by genome segments 9 and 12. A similar model has previously been reported for the rotaviruses and seadornaviruses.

  • Coltiviruses and seadornaviruses in North America, Europe, and Asia.
    Emerging Infectious Diseases, 2005
    Co-Authors: Houssam Attoui, Philippe De Micco, Fauziah Mohd Jaafar, X. De Lamballerie
    Abstract:

    Coltiviruses are tickborne viruses of the genus Coltivirus. The type species, Colorado tick fever virus (from North America), has been isolated from patients with flulike syndromes, meningitis, encephalitis, and other severe complications. Another Coltivirus, Eyach virus, has been isolated from ticks in France and Germany and incriminated in febrile illnesses and neurologic syndromes. Seadornaviruses are endemic in Southeast Asia, particularly Indonesia and China. The prototype virus of the genus, Banna virus (BAV), has been isolated from many mosquito species, humans with encephalitis, pigs, and cattle. Two other seadornaviruses, Kadipiro and Liao Ning, were isolated only from mosquitoes. The epidemiology of seadornaviruses remains poorly documented. Evidence suggests that BAV is responsible for encephalitis in humans. Infection with BAV may be underreported because it circulates in regions with a high incidence of Japanese encephalitis and could be misdiagnosed as this disease.

  • Recombinant VP6-based enzyme-linked immunosorbent assay for detection of immunoglobulin G antibodies to Eyach virus (genus Coltivirus)
    Journal of clinical virology : the official publication of the Pan American Society for Clinical Virology, 2004
    Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, X. De Lamballerie
    Abstract:

    Background: Eyach virus (EYAV) is a tick-borne virus belonging to genus Coltivirus, family Reoviridae. It was isolated in Germany and France and has been suspected to be responsible for neurological diseases in humans. To date, there has been no relatively rapid and relatively specific serological assay for EYAV. Objectives: To develop an ELISA for EYAV, suitable for epidemiological and/or diagnostic purposes. This ELISA should allow to distinguish between infections with EYAV and the related Colorado tick fever virus (CTFV). Study Design: VP6, VP7 and VP12 of Eyach virus (the three proteins most divergent between EYAV and CTFV) were expressed in bacteria using the pGEX-4T-2 vector. A partial sequence of VP6 (designated pVP6) was chosen to develop an ELISA for detecting anti-EYAV IgG antibodies in serum. This choice was based on two observations: (i) the homologous VP7 protein of CTFV was successfully used as a target for detecting antibodies to CTFV (the VP7 showed the highest reactivity to an anti-CTFV antibody among all CTFV expressed proteins); (ii) to distinguish infection with EYAV from a CTFV infection: the expressed sequence was chosen within a region which is highly divergent (49% of amino acid identity) from the homologous VP7 sequence of CTFV. Results and conclusions: pVP6 was shown to be the most reactive among the three expressed proteins. The elaborated pVP6 ELISA was evaluated with 340 sera of French blood donors, and found to exhibit a specificity of 100% (no false positives). Furthermore, no cross reaction was detected with antibody to CTFV, thus permitting us to distinguish between infections by either virus. The use of this recombinant protein for serological assays is a good alternative to the use of native EYAV antigen due to the extremely low productivity of the virus in cell culture, and the requirement for suckling mice. This ELISA will be useful to clarify the epidemiological status and the suspected pathogenicity of the virus.

  • Recombinant VP7-Based Enzyme-Linked Immunosorbent Assay for Detection of Immunoglobulin G Antibodies to Colorado Tick Fever Virus
    Journal of Clinical Microbiology, 2003
    Co-Authors: Fauziah Mohd Jaafar, Houssam Attoui, Philippe De Micco, Pierre Gallian, Philippe Biagini, Jean-françois Cantaloube, X. De Lamballerie
    Abstract:

    VP6, VP7, VP9, VP10, VP11, and VP12 of Colorado tick fever virus (CTF virus), a virus member of the genus Coltivirus, family Reoviridae, were expressed in bacteria with the pGEX-4T-2 vector. A partial sequence of VP7 (designated pVP7) was chosen to elaborate an enzyme-linked immunosorbent assay (ELISA) for detecting anti-CTF virus immunoglobulin G (IgG) antibodies in humans. This was based on two observations: (i) among all expressed proteins, pVP7 showed the highest immunoreactivity to an anti-CTF virus hyperimmune ascitic fluid; (ii) to provide the highest selectivity of antibody detection, the expressed sequence was chosen within a region which is highly divergent (49% amino acid identity) from the homologous sequence of another Coltivirus, the Eyach virus. The pVP7 ELISA was evaluated with 368 serum samples from French blood donors and found to provide 98.1% specificity. Assays with the Calisher set of human serum samples, positive for anti-CTF virus antibodies (C. H. Calisher, J. D. Poland, S. B. Calisher, and L. A Warmoth, J. Clin. Microbiol. 22:84-88, 1985), showed that the pVP7 ELISA provided 100% sensitivity for the tested population. After elaboration of recombinant-protein-based ELISAs for diagnosis of infections with members of the viral genera Orbivirus, Orthoreovirus, and Rotavirus, it was shown that a recombinant protein could be used to detect antibodies to the human pathogen Colorado tick fever virus.