Nothing suffers virus and malware problems like Windows.

I have used Linux for ten years without using any antivirus protection and
have had an always on broadband connection and am a heavy user of the
internet. There are reasons to use AV protection, such as protecting friends
who use Windows by not passing on viruses, but because it is not a problem
with Linux, Linux AV applications are hard to set up and use. You need to
scan files manually or set up a cron job to scan your system at intervals.
They do not scan in the background because there is no need.

Malware also is not a problem. Linux is sandboxed. You user area might
become infected file by file, but the system can't be compromised, if you
follow Linux protocols and do not run as root. For this reason Ubuntu uses
sudo and prevents root login. There are a few rootkits that affect Linux but
if you follow protocol you are safe. You need to be stupid to provide
password access to enable yourself to get caught. If you are worried about
others doing this (children) then do not give them your password but set up
a user account for them without admin privileges (not members of sudoers
group). Keep yourself as the lone admin account.