Like many recent viruses, Nyxem tries to spread by making people open attachments on e-mail messages that are infected with the destructive code.
The subject lines and body text of the various messages Nyxem uses vary, but many falsely claim that pornographic videos and pictures are in the attachments.
On infected machines the virus raids address books to find e-mail addresses to send itself to.
The virus also tries to spread by searching for machines on the same local network as any computer it has compromised.
Unlike many recent viruses Nyxem is set to overwrite 11 different types of file on infected machines on the third of every month. The list of files to be over-written includes the most widely used sorts of formats.
Separately, the virus also tries to disable anti-virus software to stop it updating and can also disable the mouse and keyboard on infected machines.