Download deb package from official website:
http://free.avg.com/us-en/download.prd-alf
install it:
$ sudo dpkg avg2013flx-r3115-a6155.i386.debupdate before scanning:
$ sudo avgupdatesetup real-time protection (support only special version of Linux kernel):
$ sudo avgsetupScan whole system:
$ sudo avgscan /