Virus infection from an image file (jpg) - how to make sure i'm clean?

Virus infection from an image file (jpg) - how to make sure i'm clean?

I recently opened a downloaded jpg file - the file seemed to delete itself
after I opened it (I don't recall deleting it myself). This action alerted
me - I haven't logged in on any account since then.
My system (OS: Windows 8) is currently protected with BitDefender Total
Internet Security 2013 - set to auto-pilot mode. I received no
notification of any sort from my Security system.
I also started a full system scan with both BitDefender and MalwareBytes,
but nothing came up.
My question here is: Am I safe? Is the virus gone from the system or he
might have infected other jpg files on my hard drive? Or it might have
been nothing it the first place?
Should I fully format my system, just to be safe?
I'm pretty much in the dark now. There isn't a lot of information online
regarding jpg viruses - only that they rely on overflowing a buffer and
somehow managing to execute code hidden inside the file.