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.
Allow F-Secure Anti-Virus to disinfect the relevant files.
For more general information on disinfection, please see Removal Instructions.