Any way to clear the Brontok Worm off my flash drive?

'Twas about three years ago when that trash appeared in my mom's laptop. I just so happened to plug my flash drive in one day when the popup about the “near-extinct” species of eagle flashed for the first time. At the time, I didn't know what it said until I did some research on the subject matter and found out that the Brontok eagle is actually of least concern over in the mid-Asian area. By then I knew the message was a hoax, but, for a while, Mom didn't do anything about it until about two months later (hey, we're practically broke here, so no blame, please!) when she got Malwarebytes Anti-Malware, which seemed to work on the laptop. However, the Worm still remains in my flash drive to this day, proven by the fact that I temporarily infected my brother's laptop as well, obvious symptoms showing DAYS later, and I've not seen any questions, much less any answers, to this particular subject.