Your smart phone could be dangerous for your company

Everyone uses smart phones in todays world,  we mostely have our social and professional networks enabled on our phones like facebook and linkedin.
In todays world it might be pissible that a hacker can easily identify that this perticular phone belongs to an employee of which company. We already have this information in our phones through linkedin and facebook profiles. It can also be possible that he places a silent virus on your phone and as soon as you connect your phone as a USB device it activates that virus and then you can imagine what can be done to your home or company network. Many companies have suffered such attackes in past and the owner of those devices never knew they were carrying such deadly viruses.
Safe way could be not allow any usb connections in your organization but that is not convinient, anti virus softwares on mobiles are not that good. What else can be done to minimize the effect of this upcoming threat or may be its already there?
Any comments/suggeastions are welcome.