Archives of Virology

, Volume 158, Issue 6, pp 1425–1432

Virus nomenclature below the species level: a standardized nomenclature for laboratory animal-adapted strains and variants of viruses assigned to the family Filoviridae

  • Jens H. Kuhn
  • Yiming Bao
  • Sina Bavari
  • Stephan Becker
  • Steven Bradfute
  • J. Rodney Brister
  • Alexander A. Bukreyev
  • Yíngyún Caì
  • Kartik Chandran
  • Robert A. Davey
  • Olga Dolnik
  • John M. Dye
  • Sven Enterlein
  • Jean-Paul Gonzalez
  • Pierre Formenty
  • Alexander N. Freiberg
  • Lisa E. Hensley
  • Anna N. Honko
  • Georgy M. Ignatyev
  • Peter B. Jahrling
  • Karl M. Johnson
  • Hans-Dieter Klenk
  • Gary Kobinger
  • Matthew G. Lackemeyer
  • Eric M. Leroy
  • Mark S. Lever
  • Loreen L. Lofts
  • Elke Mühlberger
  • Sergey V. Netesov
  • Gene G. Olinger
  • Gustavo Palacios
  • Jean L. Patterson
  • Janusz T. Paweska
  • Louise Pitt
  • Sheli R. Radoshitzky
  • Elena I. Ryabchikova
  • Erica Ollmann Saphire
  • Aleksandr M. Shestopalov
  • Sophie J. Smither
  • Nancy J. Sullivan
  • Robert Swanepoel
  • Ayato Takada
  • Jonathan S. Towner
  • Guido van der Groen
  • Viktor E. Volchkov
  • Victoria Wahl-Jensen
  • Travis K. Warren
  • Kelly L. Warfield
  • Manfred Weidmann
  • Stuart T. Nichol
Virology Division News

DOI: 10.1007/s00705-012-1594-2

Cite this article as:
Kuhn, J.H., Bao, Y., Bavari, S. et al. Arch Virol (2013) 158: 1425. doi:10.1007/s00705-012-1594-2

Abstract

The International Committee on Taxonomy of Viruses (ICTV) organizes the classification of viruses into taxa, but is not responsible for the nomenclature for taxa members. International experts groups, such as the ICTV Study Groups, recommend the classification and naming of viruses and their strains, variants, and isolates. The ICTV Filoviridae Study Group has recently introduced an updated classification and nomenclature for filoviruses. Subsequently, and together with numerous other filovirus experts, a consistent nomenclature for their natural genetic variants and isolates was developed that aims at simplifying the retrieval of sequence data from electronic databases. This is a first important step toward a viral genome annotation standard as sought by the US National Center for Biotechnology Information (NCBI). Here, this work is extended to include filoviruses obtained in the laboratory by artificial selection through passage in laboratory hosts. The previously developed template for natural filovirus genetic variant naming (<virus name> <isolation host-suffix>/<country of sampling>/<year of sampling>/<genetic variant designation>-<isolate designation>) is retained, but it is proposed to adapt the type of information added to each field for laboratory animal-adapted variants. For instance, the full-length designation of an Ebola virus Mayinga variant adapted at the State Research Center for Virology and Biotechnology “Vector” to cause disease in guinea pigs after seven passages would be akin to “Ebola virus VECTOR/C.porcellus-lab/COD/1976/Mayinga-GPA-P7”. As was proposed for the names of natural filovirus variants, we suggest using the full-length designation in databases, as well as in the method section of publications. Shortened designations (such as “EBOV VECTOR/C.por/COD/76/May-GPA-P7”) and abbreviations (such as “EBOV/May-GPA-P7”) could be used in the remainder of the text depending on how critical it is to convey information contained in the full-length name. “EBOV” would suffice if only one EBOV strain/variant/isolate is addressed.

Introduction

Modern molecular virology, medical countermeasure development, and epidemiology are increasingly dependent on electronic databases that make exponentially increasing datasets, such as genomic sequence information, accessible and easy to interpret. Efforts to improve databases such as GenBank or efforts to develop novel databases (which in turn often are dependent on GenBank information) are often hindered due to lack of standardized nomenclature and classification systems for particular datasets. This is especially true for virology. The International Committee on Taxonomy of Viruses (ICTV, http://www.ictvonline.org) was tasked by the International Union of Microbiological Societies (IUMS) to make decisions on matters of virus classification and nomenclature for increased efficiency and consistency in the assignment of individual viruses to taxa (orders, families, subfamilies, genera, and species). However, the ICTV is currently not responsible for the nomenclature of viruses and their strains, variants, and isolates. This task is usually designated to the ICTV Study Groups, which serve as advisory committees. Fauquet observed correctly that it “is de facto accepted by the virologists that there is no homogeneity in the demarcation criteria, nomenclature and classification below the species level, and each specialty group is establishing an appropriate system for its respective family” [9]. Unfortunately, this also means that the naming of viruses and of their strains, variants, and isolates is more or less arbitrary and differs for viruses of one family to those of another. Recently, several ICTV Study Groups and other experts, including those of the US National Center for Biotechnology Information (NCBI), have begun to develop more consistent naming schemes for virus strains, variants, and isolates in anticipation of increased submissions of population genomic sequences of viruses to databases resulting from increased availability of deep-sequencing technologies. The most notable naming scheme was developed by the Rotavirus Classification Working Group (RCWG) for rotaviruses in conjunction with the development of a new electronic database [30]. Members of the ICTV Filoviridae Study Group and many other filovirus experts have adopted most of the RCWG’s suggestions and have recently published a similar scheme for natural (aka, wild-type or naturally-occurring) filoviruses [25]. Here, it is proposed to expand this naming scheme to filoviruses generated by artificial selection through serial passages in laboratory hosts.

Summary of nomenclature below the species level for natural filoviruses

The current, ICTV-accepted, taxonomy for filoviruses is summarized in Table 1 [1, 23, 24]. In terms of natural filoviruses, it was agreed that the term “strain” is currently not applicable [25]. Natural filovirus variants were defined as follows:
Table 1

Summary of the current filovirus taxonomy as endorsed by the ICTV Filoviridae Study Group and accepted by the ICTV

Current taxonomy and nomenclature (Ninth ICTV Report and updates) [1, 23, 24]

Previous taxonomy and nomenclature (Eighth ICTV Report) [10]

Order Mononegavirales

Order Mononegavirales

 Family Filoviridae

 Family Filoviridae

  Genus Marburgvirus

  Genus Marburgvirus

   Species Marburg marburgvirus

   Species Lake Victoria marburgvirus

    Virus 1: Marburg virus (MARV)

    Virus: Lake Victoria marburgvirus (MARV)

    Virus 2: Ravn virus (RAVV)

 

  Genus Ebolavirus

  Genus Ebolavirus

   Species Taï Forest ebolavirus

   Species Cote d’Ivoire ebolavirus [sic]

    Virus: Taï Forest virus (TAFV)

    Virus: Cote d’Ivoire ebolavirus [sic] (CIEBOV)

   Species Reston ebolavirus

   Species Reston ebolavirus

    Virus: Reston virus (RESTV)

    Virus: Reston ebolavirus (REBOV)

   Species Sudan ebolavirus

   Species Sudan ebolavirus

    Virus: Sudan virus (SUDV)

    Virus: Sudan ebolavirus (SEBOV)

   Species Zaire ebolavirus

   Species Zaire ebolavirus

    Virus: Ebola virus (EBOV)

    Virus: Zaire ebolavirus (ZEBOV)

   Species Bundibugyo ebolavirus

 

    Virus: Bundibugyo virus (BDBV)

 

  Genus Cuevavirus*

 

   Species Lloviu cuevavirus*

 

    Virus: Lloviu virus (LLOV)

 

* Taxa proposed to and provisionally approved by the ICTV Executive Committee

“A natural genetic filovirus variant is a natural filovirus that differs in its genomic consensus sequence from that of a reference filovirus (the type virus of a particular filovirus species) by ≤10% but is not identical to the reference filovirus and does not cause an observable different phenotype of disease (filovirus strains would be genetic filovirus variants, but most genetic filovirus variants would not be filovirus strains if a strain definition would be brought forward)” [25].

The definition for natural filovirus isolates is:

“A natural filovirus isolate is an instance of a particular natural filovirus or of a particular genetic variant. Isolates can be identical or slightly different in consensus or individual sequence from each other” [25].

Templates were proposed for naming individual natural filovirus variants and isolates for a) Materials and Methods sections of manuscripts (full-length designations); b) alignment and phylogram figures (shortened designations); and c) flow-text (abbreviations) [25]. These templates are generally organized in the order <virus name> <isolation host-suffix>/<country of sampling>/<year of sampling>/<genetic variant designation>-<isolate designation>. Suffixes were proposed to be used for natural filoviruses sequenced directly from the matrix of the initially infected organism in the absence of in vitro propagation (“-wt”), for filoviruses sequenced from cell or tissue cultures (“-tc”), for filoviruses sequenced only partially (“-frag”), or for unsequenced filoviruses not available for study anymore due to loss or destruction (“-hist”).

Nomenclature below the species level for laboratory filoviruses

There are several non-natural filoviruses. For instance, Marburg virus (MARV), Ravn virus (RAVV), and Ebola virus (EBOV) have been passaged through adult rodents, such as laboratory mice and guinea pigs (Cavia porcellus Linnaeus, 1758), which do not develop disease upon exposure to natural (wild-type) filoviruses and which are not known to be infected by filoviruses in nature. Serial passaging in these rodents, however, culminated in filoviruses that cause disease and death (for studies on adaptation see, for instance, [2, 58, 1118, 2022, 2629, 3139, 41, 42]), and recent studies correlated this evolution with specific changes in the genomes of these viruses [3, 28, 29, 39, 40]. Artificial selection results in filovirus laboratory variants that need to be distinguished from naturally occurring variants. Since natural filoviruses do not cause disease in standard adult laboratory rodents, rodent-adapted virus variants that do cause disease are clearly phenotypically different and therefore warrant designation as laboratory strains (for a more thorough discussion on the term “strain” see [25]), whereas those that do not cause disease but are characterized by genomic mutations brought on by artificial selection should be classified as laboratory variants.

Definition of “filovirus laboratory strain”:

A filovirus laboratory strain is a genetically stable filovirus laboratory variant that evolved via artificial selection through serial passaging of a natural filovirus and causes disease in an animal that does not develop disease upon infection with the natural (wild-type) virus. The extent of genomic sequence variation is irrelevant for the classification of a variant as a strain. "Genetically stable” means that a genomic area associated with strain characteristics needs to be maintained by the virus over several rounds of replication in the laboratory host, rather than being a random mutation that occurs and disappears over time.

The definitions for filovirus laboratory variants and isolates follow those proposed for natural filoviruses:

Definition of “filovirus laboratory variant”:

A filovirus laboratory variant is a mutant natural genetic filovirus variant that
  1. a)

    evolved through serial passaging of a reference filovirus in a laboratory host;

     
  2. b)

    is ≤10% different but is not identical in sequence with the natural reference filovirus; and

     
  3. c)

    does not necessarily differ from the natural reference filovirus in infection phenotype.

     

Definition of “filovirus laboratory isolate”:

A filovirus laboratory isolate is an instance of a particular filovirus laboratory strain or variant. Isolates can be identical or slightly different in consensus or individual sequence from each other.

We propose to designate full-length and shortened designations and abbreviations for filovirus laboratory strains/variants/isolates according to the templates published for natural filovirus variants/isolates [25]. The suffix field should be “-lab” (for “laboratory-adapted”) or a combination of “-lab” and other prefixes established in [25] if necessary (for instance, “-lab_hist”, “-lab_seq”):

Full-length designation

<virus name> <strain>/<isolation host-suffix>/<country of sampling>/<year of sampling>/<genetic variant designation>-<isolate designation>
  • the virus name should be given in full, as outlined recently [23, 24]. For instance: “Marburg virus,” “Ebola virus,” “Sudan virus”

  • the strain field should contain the abbreviation of the institute at which the strain was developed (Table 2)
    Table 2

    Proposed abbreviations for BSL-4 institutes with filovirus research programs for the <strain> field in names of laboratory animal-adapted filovirus strains*

    Institute

    Proposed <strain> field abbreviation

    Australian Animal Health Laboratory (AAHL), Geelong, Victoria, Australia

    AAHL

    Bernhard Nocht Institute for Tropical Medicine (BNI), Hamburg, Germany

    BNI

    Centers for Disease Control and Prevention (CDC), Atlanta, Georgia, USA

    CDC

    Centre International de Recherches Médicales de Franceville (CIRMF), Franceville, Gabon

    CIRMF

    Defence Science and Technology Laboratory (DSTL), Porton Down, Salisbury, UK

    DSTL1

    Galveston National Laboratory (GNL), National Biocontainment Facility and Robert E. Shope Laboratory, University of Texas Medical Branch (UTMB), Galveston, Texas, USA

    UTMB

    Health Protection Agency (HPA) Centre for Emergency Preparedness and Response, Porton Down, Salisbury, UK

    CEPR1

    Integrated Research Facility at Fort Detrick (IRF-Frederick), Fort Detrick, Frederick, Maryland, USA

    IRF-F

    Laboratoire P4 Jean Mérieux INSERM

    INSERM

    National Biodefense Analysis and Countermeasures Center (NBACC), Fort Detrick, Frederick, Maryland, USA

    NBACC

    National Emerging Infectious Diseases Laboratory (NEIDL), Boston University, Boston, Massachusetts, USA

    NEIDL

    National Institute for Communicable Diseases of the National Health Laboratory Service (NICD), Sandringham-Johannesburg, Gauteng, South Africa

    NICD1

    National Microbiology Laboratory—Public Health Agency of Canada (NML), Winnipeg, Manitoba, Canada

    NML

    Institut für Virologie—Philipps-Universität Marburg, Marburg, Hesse, Germany

    UMR

    Republican Research and Practical Center for Epidemiology and Microbiology (RRPCEM), Minsk, Republic of Belarus

    RRPCEM1

    Rocky Mountain Laboratory Integrated Research Facility (RML-IRF), Hamilton, Montana, USA

    RML-IRF

    State Research Center for Virology and Biotechnology “Vector” (SRCVB “Vector”), Koltsovo, Nobosibirsk Oblast, Russia

    VECTOR

    Texas Biomedical Research Institute, San Antonio, Texas, USA

    TBRI1

    United States Army Medical Research Institute of Infectious Diseases (USAMRIID), Fort Detrick, Frederick, Maryland, USA

    USAMRIID

    Virological Center of the Research Institute of Microbiology, Sergiev Posad, Moscow Oblast, Russia

    VC

    * Only institutes that have been, are, or will be majorly involved with filovirus research are listed here. Abbreviations for other institutes can be suggested by their investigators when a name for a filovirus strain needs to be created

    1These institutes have undergone name changes over the years. We recommend that researchers use the abbreviations in use at a particular time for filovirus strain/variant/isolate names created at that time. For instance, MRE and DERA were pervious abbreviations for the laboratories now referred to as DSTL; CAMR preceded CEPR; SRIEM preceded RRPCEM etc.

  • the isolation host should be provided in one word in the format “First letter of genus name.full name of species descriptor” of the laboratory host, but remain unitalicized to denote the fact that the virus was isolated from an entity and not from a taxon [4]. For instance: “C.porcellus” (member of the species Cavia porcellus). Laboratory mice and some other laboratory animals cannot be assigned to a species. Consequently, this field should be filled with the official strain designation of the animal used for the experiments – in the case of laboratory mice and laboratory rats in accordance with the most recent “Guidelines for Nomenclature of Mouse and Rat Strains”, e.g. “C57BL/6” or “BALB/c” [19]

  • the country of sampling field should contain the same information provided as in the field for the natural (wild-type) virus

  • the year of sampling field should contain the same information provided as in the field for the natural (wild-type) virus

  • the genetic variant designation-isolate designation field should contain the same information provided in the same field for the natural (wild-type) virus connected by a hyphen to a laboratory isolate descriptor. For instance: “Mayinga-GPA-P7”

Example for the full-length designation of an isolate in the method section of a manuscript:

“Ebola virus VECTOR/C.porcellus-lab/COD/1976/Mayinga-GPA-P7”.

Shortened designation

<virus name abbreviation> <strain>/<isolation host-suffix>/<country of sampling>/<year of sampling>/<genetic variant designation>-<isolate designation>
  • the virus name abbreviation should be accepted by the ICTV Filoviridae Study Group, as outlined recently [23, 24]. For instance: “MARV,” “EBOV,” “SUDV”

  • the strain field should contain the abbreviation of the institute at which the strain was developed (Table 2)

  • the isolation host should be provided in a four-letter format “First letter of genus name.first three letters of species descriptor” of the laboratory host. For instance: “C.por” (member of the species Cavia porcellus). Laboratory mice and some other laboratory animals cannot be assigned to a species. Consequently, this field should be filled with the official strain designation abbreviation of the animal used for the experiments – in the case of laboratory mice and laboratory rats in accordance with the most recent “Guidelines for Nomenclature of Mouse and Rat Strains”. For instance, “B6” for C57BL/6 mouse strains or “C” for “BALB/c” mouse strains [19]

  • the country of sampling field should contain the same information provided as in the field for the natural (wild-type) virus

  • the year of sampling field should contain the same information provided as in the field for the natural (wild-type) virus

  • the genetic variant designation-isolate designation should contain the same information as provided in the field for the natural (wild-type) virus connected by a hyphen to an isolate abbreviation, e.g. “May-GPA-P7.”

Example for the shortened designation of an isolate in figures (alignments, phylograms) of a manuscript: “EBOV VECTOR/C.por/COD/76/May-GPA-P7.”

Abbreviation

<virus abbreviation>/<genetic variant designation-isolate designation>
  • the virus abbreviation should be one accepted by the ICTV Filoviridae Study Group, as outlined recently [23, 24]. For instance: “MARV,” “EBOV,” “SUDV”

  • the genetic variant designation-isolate designation should contain the same information as provided in the field for the natural (wild-type) virus connected by a hyphen to an isolate abbreviation, e.g. “May-GPA-P7”

Example for abbreviation in the text of a manuscript: “EBOV/May-GPA-P7” (if other isolates of the same genetic strain/variant/isolate are addressed in the same article); or simply EBOV (if the article only addresses work with one particular genetic strain/variant/isolate).

Usage of designations

As outlined in [25], we recommend that the full-length isolate designations always be used once in the Materials and Methods section of manuscripts. For example:

“HeLa cells in 96-well plates were infected for 1 h with Ebola virus VECTOR/C.porcellus-lab/COD/1976/Mayinga-GPA-P7 (derived from an Ebola virus, family Filoviridae, species Zaire ebolavirus, GenBank accession No. EU224440) at MOIs of 0.5, 1, or 5. Virus was obtained from the State Research Center for Virology and Biotechnology “Vector”, Koltsovo, Russia, and had been passaged twice through grivet (species Chlorocebus aethiops) kidney epithelial (Vero E6) cells before use.”

or

“Ebola virus VECTOR/C.porcellus-lab/COD/1976/Mayinga-GPA-P7 was obtained after i.m. serial passaging of Ebola virus H.sapiens-tc/COD/1976/Mayinga-ME718 in guinea pigs (Cavia porcellus), a laboratory host that is susceptible to fatal infection only after adaptation.”

As for natural filoviruses, we recommend using only the virus abbreviation in the remainder of the manuscript text (in the example above: “EBOV”) after proper introduction. Abbreviated designations should be used if several variants or isolates of one filovirus are addressed. For instance:

“Here we demonstrate that infection of guinea pigs with EBOV/May-GPA-P7 protects from subsequent infection with EBOV/May-8ms-N4”.

Creating new designations

Ideally, it is up to the investigators who developed a novel laboratory filovirus to create an appropriate isolate designation according to the scheme proposed here. A framework for creating such designations is presented in [25].

Acknowledgment

The content of this publication does not necessarily reflect the views or policies of the US Department of the Army, the US Department of Defense or the US Department of Health and Human Services or of the institutions and companies affiliated with the authors. This work was funded in part by the Joint Science and Technology Office for Chem Bio Defense (proposal #TMTI0048_09_RD_T to SB). YC, JHK, and VWJ performed this work as employees of Tunnell Consulting, Inc., and MGL as an employee of Lovelace Respiratory Research Institute, both subcontractors to Battelle Memorial Institute under its prime contract with NIAID, under Contract No. HHSN272200200016I. This research was also supported in part by the Intramural Research Program of the NIH, National Library of Medicine (YB and JRB).

Copyright information

© Springer-Verlag Wien (outside the USA) 2013

Authors and Affiliations

  • Jens H. Kuhn
    • 1
  • Yiming Bao
    • 2
  • Sina Bavari
    • 3
  • Stephan Becker
    • 4
  • Steven Bradfute
    • 5
  • J. Rodney Brister
    • 2
  • Alexander A. Bukreyev
    • 6
  • Yíngyún Caì
    • 1
  • Kartik Chandran
    • 7
  • Robert A. Davey
    • 8
  • Olga Dolnik
    • 4
  • John M. Dye
    • 3
  • Sven Enterlein
    • 9
  • Jean-Paul Gonzalez
    • 10
    • 11
  • Pierre Formenty
    • 12
  • Alexander N. Freiberg
    • 6
  • Lisa E. Hensley
    • 13
  • Anna N. Honko
    • 3
  • Georgy M. Ignatyev
    • 14
  • Peter B. Jahrling
    • 1
  • Karl M. Johnson
    • 15
  • Hans-Dieter Klenk
    • 4
  • Gary Kobinger
    • 16
  • Matthew G. Lackemeyer
    • 1
  • Eric M. Leroy
    • 17
  • Mark S. Lever
    • 18
  • Loreen L. Lofts
    • 3
  • Elke Mühlberger
    • 19
  • Sergey V. Netesov
    • 20
  • Gene G. Olinger
    • 3
  • Gustavo Palacios
    • 3
  • Jean L. Patterson
    • 8
  • Janusz T. Paweska
    • 21
  • Louise Pitt
    • 3
  • Sheli R. Radoshitzky
    • 3
  • Elena I. Ryabchikova
    • 22
  • Erica Ollmann Saphire
    • 23
  • Aleksandr M. Shestopalov
    • 20
    • 24
  • Sophie J. Smither
    • 18
  • Nancy J. Sullivan
    • 25
  • Robert Swanepoel
    • 26
  • Ayato Takada
    • 27
  • Jonathan S. Towner
    • 28
  • Guido van der Groen
    • 29
  • Viktor E. Volchkov
    • 30
  • Victoria Wahl-Jensen
    • 1
  • Travis K. Warren
    • 3
  • Kelly L. Warfield
    • 9
  • Manfred Weidmann
    • 31
  • Stuart T. Nichol
    • 28
  1. 1.Integrated Research Facility at Fort Detrick (IRF-Frederick), Division of Clinical Research (DCR)National Institute of Allergy and Infectious Diseases (NIAID), National Institutes of Health (NIH)FrederickUSA
  2. 2.Information Engineering Branch, National Center for Biotechnology Information, National Library of MedicineNational Institutes of HealthBethesdaUSA
  3. 3.United States Army Medical Research Institute of Infectious DiseasesFrederickUSA
  4. 4.Institut für VirologiePhilipps-Universität MarburgMarburgGermany
  5. 5.University of New MexicoAlbuquerqueUSA
  6. 6.Department of Pathology and Galveston National LaboratoryUniversity of Texas Medical BranchGalvestonUSA
  7. 7.Department of Microbiology and ImmunologyAlbert Einstein College of MedicineBronxUSA
  8. 8.Department of Virology and ImmunologyTexas Biomedical Research InstituteSan AntonioUSA
  9. 9.Integrated BioTherapeutics, Inc.GaithersburgUSA
  10. 10.Health DepartmentInstitut de Recherche pour le DéveloppementMarseilleFrance
  11. 11.Metabiota, Inc.San FranciscoUSA
  12. 12.World Health OrganizationGenevaSwitzerland
  13. 13.Medical Countermeasure Initiative, Food and Drug AdministrationSilver SpringUSA
  14. 14.Federal State Unitary Company “Microgen Scientific Industrial Company for Immunobiological Medicines”, Ministry of Health and Social Department of the Russian FederationMoscowRussia
  15. 15.BozemanUSA
  16. 16.Special Pathogens Program, National Microbiology LaboratoryPublic Health Agency of CanadaWinnipegCanada
  17. 17.Centre International de Recherches Médicales de FrancevilleFrancevilleGabon
  18. 18.Biomedical Sciences DepartmentDstl, Porton DownSalisburyUK
  19. 19.Department of Microbiology and National Emerging Infectious Diseases LaboratoryBoston University School of MedicineBostonUSA
  20. 20.Novosibirsk State UniversityNovosibirskRussia
  21. 21.Center for Emerging and Zoonotic DiseasesNational Institute for Communicable Diseases of the National Health Laboratory ServiceSandringham-JohannesburgSouth Africa
  22. 22.Institute of Chemical Biology and Fundamental MedicineSiberian Branch of the Russian Academy of SciencesNovosibirskRussia
  23. 23.Department of Immunology and Microbial Science and The Skaggs Institute for Chemical BiologyThe Scripps Research InstituteLa JollaUSA
  24. 24.State Research Center of Virology and Biotechnology “Vector”KoltsovoRussia
  25. 25.Vaccine Research Center, National Institute of Allergy and Infectious DiseasesNational Institutes of HealthBethesdaUSA
  26. 26.Zoonoses Research UnitUniversity of PretoriaPretoriaSouth Africa
  27. 27.Division of Global EpidemiologyHokkaido University Research Center for Zoonosis ControlSapporoJapan
  28. 28.Viral Special Pathogens Branch (VSPB), Division of High-Consequence Pathogens Pathology (DHCPP)National Center for Emerging and Zoonotic Infectious Diseases (NCEZID), Centers for Disease Control and Prevention (CDC)AtlantaUSA
  29. 29.Prins Leopold Instituut voor Tropische GeneeskundeAntwerpBelgium
  30. 30.Laboratoire des Filovirus, Inserm U758Université de Lyon, UCB-Lyon-1, Ecole-Normale-Supérieure de LyonLyonFrance
  31. 31.Universitätsmedizin Göttingen, Abteilung VirologieGöttingenGermany