Taxon names are written differently from virus names

Names of viruses (the physical things you work with in the lab or that make you sick) are written differently than the names of species and other taxa (logical constructs that help us categorize viruses).

A virus species name* consists of two words written in italics with the first word consisting of the virus genus name. The second word, the species epithet, consists only of letters from the Latin alphabet and numbers. A species name should not be abbreviated. Examples:

  • The genus Iflavirus includes the species Iflavirus aladeformis.
  • Members of the species Orthoflavivirus nilense are arboviruses.
  • The species Phlebovirus napoliense has many diverse member viruses.
  • The etiological agents of poliomyelitis (poliovirus types 1, 2 and 3) are members of the species Enterovirus coxsackiepol.
  • Bellavista virus, Antequera virus, Barranqueras virus and Resistencia virus  are members of the species Orthobunyavirus bellavistaense.
  • A new bacteriophage, Salmonella phage SP6, belonging to the species Zindervirus SP6, has been isolated.
  • Alphapolyomavirus ranorvegicus is a species in the family Polyomaviridae.

A virus name should never be italicized, even when it includes the name of a host species or genus, and should be written in lower case. This ensures that it is distinguishable from a species name, which otherwise might be identical. The first letters of words in a virus name, including the first word, should only begin with a capital when these words are proper nouns** (including host genus names but not virus genus names) or start a sentence. Single letters in virus names, including alphanumerical strain designations, may be capitalized. In most texts, virus names are used much more frequently than species names and may, therefore, be abbreviated. Examples:

  • Isolates of dengue virus 2 were obtained ....
  • Detection of West Nile virus in human serum ....
  • Salmonella phage SE1 was isolated ....
  • Sida ciliaris golden mosaic virus (SCGMV) causes ....
  • Aphids transmit potato virus Y (PVY).

A higher taxon name (i.e. above the rank of species) is written as a single word with a taxon-specific suffix. Examples:

realm

...viria

subrealm

...vira

kingdom

...virae

subkingdom

...virites

phylum

...viricota

subphylum

...viricotina

class

...viricetes

subclass

...viricetidae

order

...virales

suborder

...virineae

family

...viridae

subfamily

...virinae

genus

...virus

subgenus

...virus

Like a species name, a higher taxon name is written in italics and begins with a capital letter. This differs from the convention in botany and zoology, in which taxon names above the level of genus are not italicized. Taxon names are often preceded by a taxon level identifier. Examples:

  • ... a new species in the genus Fabavirus
  • ... members of the subfamily Comovirinae
  • .... members of the family Secoviridae
  • The order Picornavirales includes viruses infecting hosts of a range of species.

A collective name for a group of viruses belonging to a higher-level taxon is neither italicized nor capitalized, even if it was derived from a proper noun. The first letter of a collective name may be capitalized if it begins a sentence.

  • ourmiaviruses, ourmiavirus
  • Guernseyviruses are distributed worldwide.
  • The guernseyviruses are distributed worldwide.
  • aparaviruses
  • the aparavirus polymerase

Note that if taxa have the same stem (e.g. Tombusvirus and Tombusviridae), this may lead to ambiguity because both groups of viruses could be referred to as tombusviruses. Some virologists use the terms stem + virads, stem + virids, stem + virins, and stem + virus to distinguish members of orders, families, subfamilies and genera, respectively.

Complex example sentences

  • Ebola virus (species Orthoebolavirus zairense; genus Orthoebolavirus; family Filoviridae; order Mononegavirales) can cause disease in humans and nonhuman primates.
  • Infection of larvae of the silkworm, Bombyx mori (Linnaeus, 1758)(family Bombycidae) with the baculovirus Bombyx mori nucleopolyhedrovirus (BmNPV) (species Alphabaculovirus bomori) is often lethal.
  • In the family Poxviridae, the subfamily Chordopoxvirinae groups together all poxviruses that infect vertebrate species, including variola virus (species Orthopoxvirus variola; genus Orthopoxvirus) which is the virus that causes smallpox, and monkeypox virus (species Orthopoxvirus monkeypox; genus Orthopoxvirus) that is the virus responsible for causing the diseases MPOX.
  • Artoviruses form a family in the haploviricotine order Mononegavirales.

*The complete rules for naming virus taxa can be found in the ICTV Code: http://ictv.global/code.
** A proper noun is a name used for an individual person, place, or organization. A common noun denotes a class of objects or a concept. Host genus names are normally considered as proper nouns because they refer to a group of unique entities but some, for example "citrus", have become common nouns because they can also describe intergeneric hybrids. Virus genus names are not considered as proper nouns when used as part of a species or virus name because they refer to a subset of the genus and not the genus as a whole.