Would this be a fair summary?
The word "virus", as used in English, is truly an English word, and should therefore be pluralised acording to English rules. Further, the Latin word "virus" had no known plural, therefore any who say that the "real" Latin plural of "virus" (in the modern sense of an individual pathogen) is viri, virii, vriacalifragilisticexpialidoci, or whatever, are in fact, just bloviating.