There is no virus by this name. However, we sometimes get queries about this, since Microsoft Office's 'Fast Find' feature creates hidden files named like this to root directory: __OFIDX.FFA, __OFIDX.FFL, __OFIDX0.FFX. This is harmless.
Based on the settings of your F-Secure security product, it will either move the file to the quarantine where it cannot spread or cause harm, or remove it.
Date Created: -
Date Last Modified: -