Nearly one in three computers scanned in April for were infected with spyware, finds a study of 421,000 computers released Wednesday by EarthLink/Webroot. Trojan horses and system monitors accounted
for 133,715 pieces of the spyware found on those computers--representing almost one in three machines. System monitors track users' computer activity; Trojan horses appear to be software programs a
user has requested but actually aid hackers in stealing computer data. The so-called Spy Audit Report found 11.3 million instances of spyware on the computers in total-an average of 26.9 pieces of
spyware per machine. The previous report in March scanned 237,200 PCs, finding 7.1 million pieces of spyware.
