Hopper virus infects .VBS files and Word documents, as well as HTML files. VBS/Hopper.A infects other .VBS files by prepending it's code to the original file.
Once detected, the F-Secure security product will automatically disinfect the suspect file by either deleting it or renaming it.
Detailed instructions for F-Secure security products are available in the documentation found in the Downloads section of our Home - Global site.
You may also refer to the Knowledge Base on the F-Secure Community site for further assistance.
Some variants of this virus family also infect HTA and HTT files. Some of them lower the security settings of IE's zones. To ensure that the virus works on all platforms, when infecting VBS and DOC files, it comments out the HTML-specific part of itself. It infects documents when closes them.
Some variants of VBS/Hopper are able to infect Excel files as well.
Technical Details:Katrin Tocheva, F-Secure