I have recently had two PCs infected with disorderstatus.ru / differentia.ru, by plugging an infected pendrive. From Google searches, it appears that it is a recent virus, or at least with recent spread.
PC1 has Win Vista, and PC2 has Win 8. Both have Avast, which detected the infections.
In PC1 (with partitions C for OS/programs and D for data), I recovered a previous Ghost image into partition C. Partition D was later scanned with Avast and reported clean.
In PC2 (again with partitions C for OS/programs and D for data), I reinstalled the OS.
My two pendrives (one infected and one... perhaps too) were reformatted to FAT16 and FAT32, in a Linux boot from CD.
I further have an external HD.
Is there a way to know for sure if the infection is gone forever?
My concern is due to the fact that there are BIOS rootkits, and perhaps other beasts around that are masters of disguise.
I would appreciate getting info specific to the infection I got, in addition to possibly generic comment which might apply.