Until you find that your images are most likely infected too. That happened to me recently. I could not get rid of a persistent infection that kept showing up no matter what tool I used to try and remove it. In the end, I decided to restore from my most recent image. All seemed fine until it wasn't. That image was also infected. Same for the prior image to that (I always keep two revisions of Ghost Image sets around).

In the end, I couldn't trust my system so I reinstalled everything. On the plus side, I now have way more free space on my C: drive because I didn't reinstall everything that I had previously installed.