Boston (ECN) - A computer worm virus has hit nearly 20 million PCs worldwide running on the Windows operating system.

The new worm virus has hit PCs in the U.S., Britain, and other locations.

The virus goes by many names including Conficker, Kido, or Downadup.

To this point, it has hit 15 million PCs runing on Widows operating systems.

It can spread via web sites, USB memory sticks, e-mail, etc.

A patch was released by Microsoft to fix this, but it was not downloaded

To protect yourself, users are used to update antivirus software, and download the Microsoft patch MS08-067.