I've been doing a lot of virus stuff lately, and I came up with this idea. There should be a refvar to tell how many mkvirus commands are in an opponent's DNA. It would work similar to how refvenom tells the number of strvenom commands in the DNA.
This would allow a robot to determine if another robot is infected with a virus. For example, a robot might not normally attack conspecs, but could choose to attack infected conspecs to help prevent more infections.
Also, for symmetry's sake, there could also be a myvar which does a similar thing.