Security experts have detected a virus that targets Apple's Mac OS X systems.

Although largely harmless, researchers are referring to OSX.Macarena as a "wake up call to Mac users".

Symantec has classified the virus as a level-one 'very low' threat, as it lacks a 'payload' or any sort of malicious instructions other than simply to replicate itself.

The security firm said that, once OSX.Macarena is launched, it infects every file located in the same folder. At the time this article was written, Symantec confirmed that there were fewer than 50 confirmed cases of infection.

Kelly Martin, group project manager at Symantec's security response unit, told vnunet.com that Mac users need to be vigilant about the threat of attacks. 

She urged all Macintosh users to ensure that they have up-to-date antivirus software on their computers.

"This was a proof-of-concept. OSX.Macarena does not have a payload, so there is not a danger of people having a problem today, but it is certainly a warning sign that threats like this could come," said Martin.

The virus author may well have had this in mind, according to Martin. "We think it could be someone trying to prove that the Mac is not as secure as people think it is," she said.