Rival Network Associates Technology Inc. said the virus had surpassed last August's Sobig.F in the speed with which it traveled, and estimated the latest virus had infected between 100,000 and 300,000 computers.
"It's the fastest spreading e-mail virus ever," Craig Schmugar, virus research manager for Network Associates said. "Sobig.F was out quite a while before it hit its peak numbers, whereas this virus right from the early stages of discovery reached very large volumes of e-mail."
Postini Inc., which cleanses e-mail before it reaches the networks of corporate clients, said it was intercepting 330,000 infected e-mails an hour. As of Monday, the Redwood City, Calif.-based, company had quarantined more than 8 million messages.
By comparison, Postini intercepted 1,400 e-mails infected with Sobig.F on its first day, and 3.5 million the second, Scott Petry, vice president of products and engineering at Postini, said.