This is a fast infector, which infects COM files when they are executed or accessed. Blue_Nine is a stealth virus, making the size of the infected files seem to be the original. Blue_Nine has lots of antiheuristics features, but it also contains several bugs.
Depending on the settings of your F-Secure security product, it will either automatically delete, quarantine or rename the suspect file, or ask you for a desired action.
More information on the scanning and removal options available in your F-Secure product can be found in the Help Center.
You may also refer to the Knowledge Base on the F-Secure Community site for more information.
There are several variants of Blue_Nine. The original variant (Blue_Nine.925.A) contains this text:
Blue Nine Virus by Conzouler 1994
This variant contains this text:
It's only a lil lightfearing creature
This variant does nothing but spreads.