Virus classification

The classification of viruses is based on several structural, epidemiological or medical characteristics. However, from the purely functional classification is to distinguish the formally valid taxonomy of viruses that are classified according to the virus, for example, in families, genera and species. All other classifications are partly due to historical or practical reasons some still common. The decision criteria of taxonomy and classification of viruses meets an international body called the International Committee on Taxonomy of Viruses ( ICTV ).

The classical system of virus classification

In 1962 was introduced a taxonomy of viruses by André Lwoff, Robert W. Horne, and Paul Tournier in accordance with the established by Carl Linnaeus binary classification of living things.

In it, the following taxa are similar to the taxonomy of other living beings, divided into:

The key characteristics for this classification were:

Virustaxonomie by ICTV

Important criteria in this current international most advanced and most respected Virustaxonomie include:

• The genomic structure (DNA, RNA, single-stranded, double-stranded, polarity, linear, circular, segmented)
• Shape ( symmetry) of the capsid
• The presence of a shell
• Arrangement of the genes within the genome
• Replication strategy
• Virus size

For the taxonomy disregarded, but for the combination of different viruses with common medical or epidemiological characteristics are important criteria:

• Common organisms they infect
• Common transmission routes ( eg transmission by arthropods: arboviruses )
• Similar symptoms or infection of the same organ (eg, hepatitis viruses )

Expanded see Virus taxonomy

The Baltimore classification

On the basis of the knowledge of the molecular biology of viruses, a further classification was temporarily established, which goes back to a proposal of Nobel laureate David Baltimore of 1971.

The various possibilities arise from the fact that one strand of the double-stranded DNA, as it is in all other living beings, is redundant and can be omitted. Likewise, the viral genome may also be in different forms of RNA in cells occur as an intermediate in protein synthesis. In single-stranded RNA encoding both possible directions occur. The normal direction of 5 '→ 3', is referred to as ( ) polarity, as is present in the mRNA and the reverse ( complementary ) in the direction (-), in which the RNA is present as a quasi- negative. The Baltimore classification after replication strategy is now increasingly uncommon and is almost displaced by the taxonomy of the ICTV.

The summary in orders is fairly new. There is thus far only 3 trims, and many families are still not assigned to any order. Currently, about 80 families and about 4000 species are known.

Baltimore Group I

Double-stranded DNA - dsDNA. Normal genomic form of all life.

• Order Caudovirales. Bacteriophage with schwanzartigem extension. families: Myoviridae
• Podoviridae
• Siphoviridae
• Poxviridae Chordopoxviridae orthopoxvirus
• Parapoxvirus
• Avipoxvirus
• Capripoxvirus
• Leporipoxvirus
• Molluscipoxvirus
• Yabapoxvirus

• Entemopoxvirus A
• Entemopoxvirus B
• Entemopoxvirus C

• Alphaherpesvirinae simplex virus Herpes simplex virus 1 (HSV -1) or (HHV -1)
• Herpes simplex virus 2 (HSV -2) or (HHV -2)
• Herpes B virus = ( herpesvirus simiae )

• Varicella zoster virus (VZV) or (HHV -3)
• Pseudorabies virus ( Aujeszky's disease virus )

• Cytomegalovirus Human - cytomegalovirus ( HCMV ) = - Human cytomegalovirus ( HCMV) = Human herpesvirus 5 (HHV -5)
• Bovine - cytomegalovirus = Bovine herpesvirus 4 (BHV -4)
• Felines cytomegalovirus = Feline herpes virus 2 (FHV -2)

• Mouse cytomegalovirus = mouse herpes virus 1 ( MHV -1)

• Human herpes virus 6 (HHV -6)
• Human herpes virus 7 (HHV -7)

• Lymphocryptoviren Epstein-Barr virus (EBV) Human herpes virus = 4 (HHV -4)

• Human herpes virus 8 (HHV -8)

• Orthohepadnaviren Hepatitis B virus (HBV)

Baltimore Group II

Single-stranded DNA - ssDNA ( single engl. beach ). Virions containing DNA of positive or negative polarity.

• Parvoviridae Parvovirinae Dependovirus Adeno-associated virus -2 ( AAV -2)
• Adeno-associated virus -3 ( AAV -3)
• Adeno-associated virus -5 ( AAV -5)

• Parvovirus B19

• Porcine parvovirus
• Feline parvovirus
• Canine parvovirus

• Denso virus
• Iteravirus
• ContraVirus

Baltimore Group III

Double -stranded RNA - dsRNA

• ...
• Reoviridae rotavirus
• Coltivirus Colorado tick virus

Baltimore Group IV

Positive single-stranded RNA - ss ( ) RNA. It acts directly as mRNA.

• Arteriviridae
• Togaviridae alphaviruses Chikungunya virus ( CHIKV )
• O'nyong'nyong virus ( ONNV )

• Rubivirus = rubella virus Rubella =

• Hepacivirus Hepatitis C virus (HCV)
• GB virus C GBV -C ( non-pathogenic )

• West Nile Virus
• Dengue virus
• Yellow fever virus
• Louping -ill virus
• St. Louis encephalitis virus
• Japanese B encephalitis virus
• Powassan virus
• RSSE virus
• TBE virus

• SARS -associated coronavirus (SARS -CoV )
• Coronavirus Human coronavirus 229E ( HCoV )
• Human coronavirus OC43 ( HCoV )

Baltimore Group V

Negative single-stranded RNA - ss (-) RNA. It acts as a template for mRNA synthesis.

• Order Mononegavirales. RNA is not segmented. families: Rhabdoviridae Lyssaviren Rabies virus ( RABV ) (genotype 1) = rabies virus
• Lagos bat virus Lagos bat virus = (LBV ) ( genotype 2 )
• Mokola virus ( MOKV ) (genotype 3)
• Duvenhage virus ( DUVV ) (genotype 4)
• European bat lyssavirus - bat lyssavirus = European ( EBLV 1, 2) ( genotypes 5 and 6)
• Australian bat lyssavirus - = Australian bat lyssavirus ( ABLV ) (genotype 7)

• Paramyxovirinae Respiroviren Parainfluenza virus ( 1, 3)

• Measles virus
• Rinderpest
• Canine distemper virus

• Parainfluenza virus ( 2, 4)
• Mumps virus
• Newcastle Disease Virus (NDV )

• Pneumoviruses Sincytical respiratory virus ( RSV)

• Human - Metapneumo virus ( HMPV )

• Marburg virus Lake Victoria Marburg virus

• Ebola Zaire virus
• Ebola - Sudan virus
• Ebola - Ivory Coast virus
• Ebola - Reston virus

• Order, segmented RNA. families: orthomyxoviruses Influenza viruses A Influenza virus A variant ( H1N1)
• Influenza virus A variant ( H2N2 )
• Influenza virus A variant ( H3N2)
• ( avieres ) influenza virus A variant (H5N1 ), highly pathogenic avian influenza virus ( HPAIV )
• ( avieres ) influenza virus A variant ( H7N2 ) pathogenic avian influenza virus low ( LPAIV )
• ( avieres ) influenza virus A variant ( H7N3 ) pathogenic avian influenza virus low ( LPAIV )
• ( avieres ) influenza virus A variant ( H7N7 ), highly pathogenic avian influenza virus ( HPAIV )
• ( avieres ) influenza virus A variant ( H9N2 ) pathogenic avian influenza virus low ( LPAIV )

• Influenza virus B / Victoria Line
• Influenza virus B / Yamagata - line

• Phleboviren Rift Valley fever virus
• Sandfly fever virus

• Crimean-Congo fever virus

• Hantaan virus = muerto Canyon virus
• Seoul virus
• Psospect -Hill virus
• Puumala virus ( PUU )
• Dobrava virus
• Tula virus
• Korea fever virus
• Sin Nombre virus

• Arena virus Lassa virus
• Lymphocytic choriomeningitis virus ( LCMV )

• Machupo virus

Baltimore Group VI

Positive single-stranded RNA, which is written back into DNA and integrated into the cell genome.

A family

• Retroviridae Orthoretrovirinae Alpha retrovirus
• Beta retrovirus
• Gamma retrovirus
• Delta retrovirus Human T- lymphotropic virus 1 (HTLV -1)
• Human T- lymphotropic virus 2 (HTLV -2)

• Human immunodeficiency virus type I (HIV -I)
• Human immunodeficiency virus type II (HIV -II)
• Simian immunodeficiency virus ( SIV)
• Feline immunodeficiency virus ( FIV)
• Caprine arthritis- encephalitis virus ( CAEV )
• Virus of equine infectious anemia ( EIAV )
• Maedi - visna virus ( MVV )

• Spumavirus

Baltimore Group VII

Double-stranded DNA using an RNA intermediate step of replicating.

• Hepadnaviridae such as hepatitis B virus
• Caulimoviridae, plant viruses such as the CSSV