Perhaps the other computer has something that is being flagged/counted as a virus; false positive perhaps.
Unless both computers are completely identical, then I would not expect the results to be identical. And maybe not even then depending on use history, etc...
However, I think more information may prove helpful. Being able to see the screens and virus count totals in question would be a good starting point.
Are you able to post comparative screen shots from each computer?
http://www.tomshardware.com/answers/id-2173703/post-images-tomshardware-guide.html