I was never been a big fan of anti-virus on the servers.
I believe more in limiting access & being careful.
I have however just gotten used to thinking it is needed for client workstations.
Also, I can't remember which application, but I do know portions would not work if the user wasn't the local admin. (maybe it was Solidworks)?
So AV has been running on most clients forever.
Even so I know of at least two cases were users were infected with zero day exploits anyway.