The only case where I'd use a virus scanner is when I'd host a file server for Windows systems.
Btw, ClamAV is slow and generally awful. It has many false positives that you get spammed all the time. There are also cases where it doesn't really find the virus (false negatives). It's also buggy and it's not a good sign for security product.
I'd still recommend Linux, if you want to be safe. Windows has never been designed with security in mind. It's not even a proper multiuser system.