A document containing this information can be downloaded here.
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 species name* is written in italics with the first word beginning with a capital letter. Other words only begin with a capital if they are proper nouns (including host genus names but not virus genus names**) or alphabetical identifiers. A species name should not be abbreviated. Examples:
Some host genus names may also be considered common nouns in English and can be written in lower case where they are not the first word of the species name. Example:
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:
A higher taxon name (i.e. above the rank of species) is written as a single word with a taxon-specific suffix. Examples: