ABSTRACT
According to the rules of the International Committee on Nomenclature of Viruses (ICNV), laid down in 1966 during the IX International Congress for Microbiology, the taxonomic system for viruses does not classify them by the hosts they infect, but by such criteria as chemistry (DNA or RNA viruses), symmetry (helical or cubical), and other characteristics of the virions. Consequently, viruses should no longer be grouped as viruses of bacteria, fungi, algae, mycoplasma, higher plants, invertebrate and vertebrate animals, but as members of a single "kingdom" of viruses (Virales). Lwoff and Tournier3 have presented a partial classification of all viruses according to the unified system of classification (Table 1). It utilizes the nature of the genetic material, the symmetry of the capsid, the naked or enveloped nature of the nucleocapsid, the number of capsomeres for virions with cubical symmetry, and the diameter of the nucleocapsid for virions with helical symmetry.
