http://www.csoonline.com/article/3020459/security/antivirus-software-could-make-your-company-more-vulnerable.html
Just by sending an email without you even opening it, can exploit antivirus software.
It seems the big and bloated syndrome doesn't just apply to operating systems and Flash, but antivirus programs as well.
People need to be aware that security exploits can happen with any software. Even antivirus software.