USB memory stick has 'loader.exe' constantly appearing

Hello

I have a USB memory stick and everytime I insert it into a PC (running
WinXP pro) symantec finds 3 x 'loader.exe' on it.

I have formmatted the stick a number of times but each time Auto
protect keeps finding this worm.

Could it be that there is something built into the memory stick that
formatting will not wipe, there is nothing showing on the stick
itself, but on 3 different machines the antivirus has found this
trojan horse 'loader.exe'

Maybe I should throw it away.