You can check the quarantine area to get the virus name and then search the internet for any information on that virus type..
--I wouldn't automatically delete files: it is best to check even if it only satisfies your curiosity about the virus detected
Once you are comfortable with ClamAV operations, you can decide if you then want to delete instead of quarantine the file..
--also since you will already (usually for your own connection) be behind an ISP firewall and spam filters (you don't have to pay for it, since they most likely have to do that in any case to defend their own network: the reason they block port 25 for local email transmission)
And of course, Linux/Ubuntu already comes with UFW (uncollimated FireWall): a software firewall
--your local addition to any ISP or other connection type's security..
If I got that, I would probably run clamav directly again without being connected to the internet and see if it detects a virus name??https://en.wikipedia.org/wiki/Clam_AntiVirus
--there are possibly some GUI for the desktop, you could use, if you don't want to learn the command line (terminal: shell (bash) commands..)
It is also true, that the likely virus, if it is real not a false positive would be a windows file type, such as an outlook email or a windows browser (Firefox or IE)
--if you were only in Linux and not using windows, then I don't know: Linux and Apple OSX tend to get very much fewer real viruses or worms than Windows OS
Microsoft says this is because windows OS is more ubiquitous: another opinion is that windows OS is a patch job with many elements that is less integrated (as a system) than it appears to be
--that is my view as well, since i am aware of some there development of the OS
To calm your mindhttps://en.wikipedia.org/wiki/Linux_mal ... ic_threats
The following is a partial list of known Linux malware. However, few if any are in the wild, and most have been rendered obsolete by Linux updates or were never a threat. Known malware is not the only or even the most important threat: new malware or attacks directed to specific sites can use vulnerabilities previously unknown to the community or unused by malware
In the wild mind ubiquitous running on the internet for any targets available
You may wish to install chkrootkithttp://www.linuxforu.com/2011/10/chkroo ... my-within/
--a rootkit scanner for Linux
Also unless the virus or worm etc is a remote exploit, there is little if anything to worry about
--local exploits are managed by using a proper password/passphrase and possibly encrypting your /home directory (folder) space
Truecrypt is well known windows application which is also available for Linux, you may be familiar with it..