Contrary to popular belief, Linux OS's need to be secured just as Windows does. Although upon the install process, one will read, no more defragging, no more maintenance, no need for an AV, that last option is simply not true. A Linux install, although hard to infect the OS itself unless one is logged in a root (same as administrator in Windows), can pickup viruses & malware & be passed on to Windows computers.
Fortunately, there are a couple of options for Linux users to protect their computers. One, ClamTK, is free of charge, while not an active virus blocker, it's scanner is powerful. If it's dual booting with Windows, it can scan the Windows partition, one at a time. ClamTK can be found here:
ClamTk Virus Scanner
Another option, but a paid one, is ESET NOD32 for Linux:
ESET NOD32 For Linux (Ubuntu)
Don't believe the hype, Linux installs are as easily infected as Windows is. Even those who concedes that while Linux OS's can carry infections, just because it can't break the OS, doesn't bog it down, that's excuse enough not to bother with security. They simply don't care about infecting other's computers. That's reckless computing, having no disregard for others.
I use Ubuntu & Mint (second to Windows 7), and I take security just as serious with those OS's as I do with Windows. After using either, I first run BleachBit (identical to CCleaner), then I do what's called a recursive (full) scan of my home folder, where my browsers are at. I've only found one thing, a false positive, but the scan only takes 5 minutes tops, and I don't worry about spreading infections across the net.
BleachBit can be ran on Windows also. Here it is, but watch out, it's powerful software.
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