In the last few weeks I've noticed my email has been automatically sending out spam/viral emails to some of my contacts. It seems to be sending out multiple emails (every few minutes) to one particular contact and I only realised when o was checking my sent mail! I mainly use my phone to look at mail and I've run 3 antivirus programme scans to no avail. 

What can I do to get rid of this virus?! Please help!!

Sb