Fonte: http://askubuntu.com/questions/250290/how-do-i-scan-for-viruses-with-clamav/

 

At first you have to update the virus definitions with:

sudo freshclam

Then you can scan for viruses.

clamscan OPTIONS File/Folder 

If necessary start with root permissions: sudo clamscan.

Examples:

• To check all files on the computer, displaying the name of each file:

  clamscan -r /
  

• To check all files on the computer, but only display infected files and ring a bell when found:

  clamscan -r --bell -i /
  

• To scan all files on the computer but only display infected files when found and have this run in the background:

  clamscan -r -i / &
  

  Note – Display background process’s status by running the jobs command.

• To check files in the all users home directories:

  clamscan -r /home
  

• To check files in the USER home directory and move infected files to another folder:

  clamscan -r --move=/home/USER/VIRUS /home/USER
  

• To check files in the USER home directory and remove infected files (WARNING: Files are gone.):

  clamscan -r --remove /home/USER
  

• To see more options:

  clamscan --help