Ha, interesting way of additional protection for your roles, running in Windows Azure. This was just released:

MEP for Windows Azure is a software package that extends the Windows Azure SDK by adding an antimalware plugin. The antimalware plugin provides a means of enabling antimalware protection in the underlying virtual machines (VMs) atop which the Windows Azure hosted service runs. Once AM is enabled as part of the service definition, the AM components will be installed, configured, and started within each role instance VM when it is spun up by the Windows Azure Fabric Controller.”

The download page containing the plugin and documentation can be found here: http://www.microsoft.com/download/en/details.aspx?id=29209.