Hello,
This Threat is a New Threat Discovered: May 24, 2011
Could let us know the Symptoms?
X97M.Romnum is a macro virus that infects Microsoft Excel files.
What I would suggest is to :
1) Make sure you are updated with the Microsoft updates in regards to the MS Office and Operating System.
2) Make sure all the machines are Installed with the SEP with the Latest Virus Definitions on them and Run a Full Scan the network atleast once.
3) If in case, you think that the Threat is Spreading, you can get to know the source of the Threat by Enabling the Risk Tracer feature from the SEPM.
To know more on Risk Tracer, read the Following Articles:
Note: The Risk Tracer Feature would Require Network Threat Feature Installed and Enabled on all machines to work Correctly.