Here’s a question, would you need to install an AVS on a Virtual Server if the hosting system already had AVS on it?
Can the host AVS scan the VMDK? And if so, does that mean it’s protected?
hello Nick you should have called to ask me this one 
Yes you should protect VM, the OS runs within VM and therefore is subject to infection like a normal workstation/server. Without installing on the VM you are at risk of the data within the vm being infected…[if that all makes sense]
The host OS won’t pickup the VM sessions as they are in-effect secure machines. So buy some more licenses 
If you want to test for yourself goto www.eicar.com and download the test virus file while logged in to the VM machine
Give me a buzz if you need anything.
av-outsource ;D