Think of them as 24-hour bugs for your computer.

PandaLabs announced today that over half of all new viruses, worms and Trojans exist in the wild for less than a day before running out of steam.

Sadly, that's not because security companies like Panda (or AVG or Symantec) wipe them out in a flash, but because virus writers are always swiftly moving on to the next big thing.

Always wash your keyboard and mouse thoroughly

Malware authors naturally want their creations go unnoticed by users and security companies. According to Panda, just 24 hours after hackers put any strain of virus into circulation, they will modify its code so that it can continue to spread without being detected by security software.

"This is a never-ending race which, unfortunately, the hackers are still winning. We have to wait until we get hold of the malware they have created to be able to analyse, classify and combat it," said Luis Corrons, Technical Director of PandaLabs.

The race is hotting up, too. While Panda identified a staggering 18 million malware samples during the whole of 2008, the company had already spotted over 30 million pieces of malicious code in 2009, by the end of July. There are now over 37,000 new viruses, worms and Trojans appearing online every day.