An Incremental Back-up is one that is set to Back-up, all the changes that you have made to the Computer, since the previous Back-up, and to do this at regular intervals.
The bit that I don't understand.
The whole point about Back-ups is that you then have a Copy of everything; should there be a mechanical catastrophy or you download a Virus.
Now, if you were to pick-up a Virus and then the Incremental Back-up did it's bit, before you realised that you had the Virus. Surely your Back-up File would also contain the Virus and therefor be rather less than useful?
Before I do a back up (using ATI) ,or image, or clone, I: 1. Scan for virus with (in my case, Avira). 2.Scan for malware using SAS and Malawarebytes. 3. I defrag the partitions to be backed up. Then I both clone my primary drive to a slave and make images of each of two partitions to an external HD. I also make a mirror copy of my data (My Documents) to the external HD. I do not do incremental back ups (following advice on the forums); after I have verified the latest images, I delete the previous ones, then defrag the extenal HD (this takes quite a time.(I am using W7 but still prefer ATI 2010 as I am more familiar with it.)
There is a suggestion here that "normal"incremental backups are useless, i would say they are far from that if you feel the need to use this method. WHY should any virus specifically target your "incremental backup" ANSWER, it is probably not. If you fear these attacks as strongly as you do i would say your chosen A/V is not much cop...