Many Computer Viruses Become Inert After 24 Hours

More than half of computer viruses last a mere 24 hours.

Panda Security's malware detection laboratory, PandaLabs, has been analyzing the nearly 37,000 samples of new viruses, worms, Trojans and other security threats that it receives each day and found that 52 percent of them work for just 24 hours. "

Source:
http://hothardware.com/News/Many-Computer-Viruses-Become-Inert-After-24-Hours/