Virology Division News
Virology Division News
Arch Virol 143/1 (1998)
The universal system of virus taxonomy of the International
Committee on Virus Taxonomy (ICTV), including new proposals
ratified since publication of the Sixth ICTV Report in 1995
C. R. Pringle
Biology Sciences Department, University of Warwick, Coventry, U.K.
A number of new taxonomic proposals have been considered by the Executive Committee
of the International Committee on Virus Taxonomy (ICTV) since publication of its Sixth
Report in 1995 . Several of these proposals were ratified subsequently at the Plenary
Meeting of the ICTV during the Tenth International Congress of Virology in Jerusalem in
August 1996. Others have been ratified by postal ballot of the full membership of the ICTV
subsequent to a meeting of the Executive Committee of the ICTV in Strasbourg in May
1997. Table 1 presents the current version of the Universal System of Virus Taxonomy
which includes the new taxonomic proposals which have been ratified by the ICTV up to the
end of 1997 . This is an abbreviated version of the up-dated taxonomy; it does not extend
to the listing of approved virus species, a feature which is expanding rapidly. A major
revision of virus taxonomy is being undertaken currently by the individual Study Groups of
the ICTV, which is scheduled to be published as the Seventh Report of the ICTV prior to the
Eleventh International Congress of Virology in Sydney in 1999.
The order of presentation of virus taxa follows that adopted in the Sixth Report. It is
based on four criteria:
(1) the nature of the viral genome,
(2) the strandedness of the viral genome,
(3) the facility for reverse transcription, and
(4) the polarity of the virus genome.
The order of presentation does not imply any hierarchical or phylogenetic relationship. At
present viruses are classified into 189 genera. Of these, 166 are classified into 55 families.
The remaining 23 are “floating” genera which have yet to be assigned to a higher taxon.
Two Orders have been established: the order Mononegavirales to include the four families
Bornaviridae, Filoviridae, Paramyxoviridae and Rhabdoviridae, and the order Nidovirales
to include the two families Coronaviridae and Arteriviridae.
It should be noted that the genus containing potato mop top virus is recorded here as
Pomovirus, and not Potamovirus as recorded erroneously in the report of the Strasbourg
Meeting, published in the August issue of Virology Division News .