The ICTV's recommendation for how to write species and virus names. (Updated May 28, 2019)
You are correct. The use of capitalization and italics as indicated in the article above, is meant for official, ICTV-approved taxon names. Proposed, but not yet approved taxon names should be written as per the guidelines above for writing virus names.
Dear ICTV members,
I have a doubt.
Recently, in an article entitled "A major lineage of non-tailed dsDNA viruses as unrecognized killers of marine bacteria", published online on 24 January 2018, as a Letter in Nature, the authors propose the name of a new family, named Autolykiviridae. In their article, authors uses the name Autolykiviridae in italics for define it as a possible new virus family. Is right to use Autolykiviridae in italics in this case, even when this "new family" is not yet recognized by the ICTV?