From:
http://www.psychocats.net/ubuntu/security
"Conventional wisdom in the Linux community says that there are either
no or very few Linux viruses out in "the wild," and that most are just
proof-of-concept theoretical viruses. Some people recommend installing a
virus scanner like ClamAV in order to protect your Windows-using friends
from Windows viruses you might accidentally send them. I don't really
see how that's an issue, though. If you have an attachment you created
in Linux, why would it have a Windows virus in it? If your computer has
been compromised in such a way that you don't have control over what you
send other people, then you have a lot more to worry about than
spreading viruses to your Windows-using friends!

I've never heard of any spyware in Linux... ever. Still, if you're
super-paranoid, stick to software in the repositories. And if you don't
trust even the software in the repositories, why are you installing
Ubuntu at all? The operating system and the software are packaged by the
same people. "

Linux is allegedly more secure than Windows, and Ubuntu doesn't allow
you to run as root, and includes a firewall by default.
This not to say it will always be Virus and Spyware free, but I've been
running  without any AV/Anti-Spyware programs for a long time with no
problems at all, and that's the way most people use Linux.

-------- Original Message --------
Subject: Re: [PCBUILD] Any latest advice re: do/don't install SP3? / MS
updates
From: John Clemence <[log in to unmask]>
Date: Mon, October 19, 2009 9:40 am
To: [log in to unmask]

Hi,
I was fascinated to read your comments re Linux and AV, anti-spyware 
software. Can I take it that one really does not need these protections
when 
using a Linux system?
Regards,
John.

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