Microsoft announced the availability of ant-malware for Azure Cloud Services and Virtual Machines, providing real time protection from the latest threats at no additional charge.The Microsoft Antimalware Client and Service is installed by default in a disabled state in all Cloud Services. The Microsoft Antimalware Client and Service is not installed by default in the Virtual Machines platform; it is available as an optional security extension.
http://azure.microsoft.com/blog/2014/10/30/microsoft-antimalware-for-azure-cloud-services-and-virtual-machines/