OM ("OfficeMacro") is a family name for all Microsoft Office Macro
viruses. These are viruses which infect not only one Office application
but several - for example, Word and Excel.
For example, if you're looking for the description of "O97M/Jerk",
"OfficeMacro.Jerk" or "Macro.Office.Jerk" virus, see the description of
"Jerk".