Although it is nearly impossible to become "infected" by anything which can do your system any real harm, our Linux systems can, at times, be carriers of such critters, i.e., your sent email.
Moreover, we get a new kernel so often that bad code hardly stands a chance of catching up; but mainly, it is the way in which the architecture of our file system stands up to threats - the bad guys have insurmountable hassles getting in.
I run Wine (Playonlinux), to use a mandatory Windows program; and that, theoretically - being a Windows go-between - could leave a door open for critters. This is why I also have ClamAV installed, and I run it once a week. Clam is all that free and open souce is going to offer - and it should be all that you would ever need - if you even need anything. The are two packages - plus an add-on - that makes up the part of ClamAV which you would be using.
Let us know if you have any questions; and below is a bit of info. 