Which computer did the viris originate from?

Hello,
I think I gave a co-worker a viris at work. I put my thumb drive in one of the computers at work then in the co-workers computer. After that his laptop would not boot. It cost him $15 dollars to have it fixed (I live in Thailand). I am sure my thumb drive had a viris. What I would like to know without a lot of questions about the type of viris, operating systems,ete. Is there a way to prove where the viris originated from, my computer at home or the computer at work? Is there a machine address code attached to the viris or something like that would tell me that?
Thank you so much.
Barry