Although widespread virus outbreaks may be a thing of the past, the total amount of malicious software being written is on the rise, says McAfee. The security vendor added the 200,000th definition to its threat database, and it expects the total number of identified threats <A HREF="http://www.infoworld.com/article/06/07/05/HNmcafee400k_1.html">to double in another two years.</A> McAfee's antivirus products use these definitions as digital fingerprints to determine which software should not be allowed to run on a user's PC.