On the sense and senselessness of Malware cleaning

Some systems do become horribly infected and are damaged beyond repair, but for the others, the trained helpers on the security forums have access to some very powerful tools for diagnosing and digging deeply to remove whatever signs of infection that are found. Their aim is to restore a system to its pre-infected working state without having to perform re-installation. 

Prevention is always better than spending days trying to clean once infected, and backups are a must.

Just playing devil's advocate here. I would certainly rely on the advice of a trained malware remover in the event.

Follow-up question: Do you know if a full backup by Acronis of a clean system to an external HD is immune to infection? It is stored as a compressed  *.tib file that I cannot scan with any of my AV/AS programs. Just idle curiosity, against a rainy day.

If it's clean to begin with as you made the backup, I would think it would be okay. 

Thanks. It's one of those things you hope you never have to test. Acronis has a program to validate the integrity of the backup, but until you need it you never really know for sure.