How to classify viruses ? What nomenclature to use ?
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Taxonomy
The rapid evolution of knowledge in that field, the implication of an increasing number of viruses in all fields related to biology and medicine have imposed other scientific priorities than the definition of a specific vocabulary. Besides, a precise nomenclature implies a very precise classification of viruses ; but the viral taxonomy has somewhat erred before reaching its present structuring.
Progressively virus classification has been organised into species, genus and families defined by common characteristics. Plant viruses have at present 64 genus. Viruses are classified following different criteria such as their geometry, the presence or not of an envelope coat, the identity of their potential hosts, their mode of transmission or the symptoms caused. The most convenient classification is probably by the virus’s type of nucleic acid and by its mode of expression. This classification was proposed by David Baltimore, medicine Nobel prize laureate in 1975. It should be noted that none of these classifications are supposed to be phylogenetic, being given that the viruses do not share a common origin. Also note that the taxonomy of viruses is in constant revision.
Nomenclature
The nomenclature of viruses is not easy to use when one is not a virologist. Whereas the cellular organisms have a binomial terminology in Latin, the names of viruses are generally inspired by the symptoms provoked on the host.
Italics, acronyms, capital letters, how is a virus designated ?
In their formal use, the official names of viral families, subfamilies and genus are written in italics with the first letter in capital. Since 1998, this rule applies to the species. When this taxon is in italics, it means that the virus has been officially recognized by he International Committee on Taxonomy of Viruses (ICTV), official institution in charge of virus taxonomy ( to know more, please refer to the text box)
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