An antivirus software item available on Debian Linux is Clam AntiVirus. The package name is "clamav". The graphical user interface (GUI) is "clamtk".
Install Clam AntiVirus using Synaptic Package Manager:
Click on "Applications", "Accessories" and "Virus Scanner" to start Clam AntiVirus. Click on "File" to choose a file. Press "Directory" to choose a directory.
As a superuser in Terminal, type freshclam to update the virus definitions.