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The fury of the mass-mailing "NakedWife" Trojan worm was contained quickly this week with the aid of technology, corporate assistance, and media coverage, computer security companies say.

Word spread fast Tuesday about the worm, which can delete files in the Windows and system directories and has the potential to clog e-mail networks. The rapid spread of information about the virus helped contain its wrath, they say.

"We saw about ten companies that reported the virus," says Susan Orbuch, a Trend Micro spokesperson. "It really turned into a flash in the pan, in part because of the [efforts] of the security companies, the corporate community, and the media."

Security companies began getting reports on the Trojan worm from corporate users early Tuesday. The worm masks itself as a Macromedia Flash file and spreads through Microsoft Outlook, sending an e-mail message to every e-mail address in the infected user's address book. The worm goes by the names NAKEDWIFE, W32/Naked@MM, and W32.HLLW.JibJab@mm.

Infected mail comes with the subject line, "FW: Naked Wife." The body of the message reads, "My Wife never look like that :), Best Regards." The attachment is named NakedWife.exe.

When the Trojan worm is executed, it displays a Macromedia Flash window that states, "JibJab loading." While the file loads, the worm attempts to delete DLL (Dynamic Link Library), INI (initialization files), EXE (execution files), BMP (picture files), and COM (resource) files in the Windows and system directories.

A majority of the reports of the worm came from the U.S., Canada, and Europe, according to security companies.

Computer security firm Central Command says 44 corporate users reported being infected by the virus. Most of the reports had been received by 1 p.m. PST Tuesday. McAfee, a division of Network Associates, obtained about 25 acknowledgements of NakedWife from corporate customers.

Symantec, meanwhile, received 35 reports from corporate users, and about 31 of those came on Tuesday, says Stephen Trilling, director of research at Symantec. Another 4 reports came on Wednesday, he says.

Similarly, Computer Associates International saw its reports on NakedWife taper off drastically on Wednesday. A majority, if not all, of its 20 to 25 reports from corporate users came on Tuesday, says Ian Hameroff, Computer Associates' business manager for antivirus solutions.

Most viruses that have occurred recently have the potential to spread rapidly through e-mail, but they also are usually controlled quickly, Hameroff says. Greater efforts to raise awareness among users and the speedy availability of updates to virus protection software help limit the spread, he says. Early warning systems that notify network administrators when a new virus has emerged also assist in the effort, says Patrick Nolan, a virus researcher at McAfee.

For further information on viruses, worms, and Trojans, see How It Works: Viruses.