hi.experts of this team.
please look at below address:
http://www.microsoft.com/athome/security/viruses/wsc/en-us/flist.mspx
your avast virus is in the position of 4 .
AhnLab ----- first
Aladdin ----- second
Authentium -----three
ALWIL Software -----four
before three virus what 's them is better than avast ?
hope avast works best!