His point was that if you can't follow along, then you don't know much on the topic and have little advice to offer. Hepsreal didn't use any unusual abbreviations, just the standard ones that are always used in place of the whole 20 letter word.
CMV= cytomegalovirus
hhv6= human herpes virus 6
IgM= Immunoglobulin M
CD8 = cluster of differentiation 8 OR
CD8 - Wikipedia, the free encyclopedia
I don't know shit about the Epstein-Barr virus and associated abbreviations, but I've got mad Google skills.