I assume you mean that your antivirus program does not have any type of file system shield/real time scanner, not that you have no antivirus program on a pc. Good luck either way!
There is not tell about antivirus SW I have mount remote in the internet CIFS (end point is Linux server).. When I check speed via SMB share ASUS merlin so speed is about 700 KB/s. When I try it direct on the PC //server/blabla so 5 MB/s (line speed)..
Problem is while watching mo*vies via DLNA in Full HD from remote CIFS ..