First you need to disinfect/immunize their system to prevent future autorun.inf infections and then immunize the usb sticks.
1.
Flash Drive DisinfectorDownload
Flash_Disinfector.exe by sUBs from
>here< and save it to your desktop.
- Double-click Flash_Disinfector.exe to run it and follow any prompts that may appear.
- The utility may ask you to insert your flash drive and/or other removable drives including your mobile phone. Please do so and allow the utility to clean up those drives as well.
- Wait until it has finished scanning and then exit the program.
- Reboot your computer when done.
Note: Flash_Disinfector will create a hidden folder named autorun.inf in each partition and every USB drive plugged in when you ran it. Don't delete this folder...it will help protect your drives from future infection.If you can stop reinfection by immunization them it is easier to deal with the problem. USB sticks can become corrupt without any virus infection so this could be a coincidence, after all why would the malware want to corrupt what it is on and its means of dissemination.
Also see,
http://www.bleepingcomputer.com/forums/lofiversion/index.php/t176656.html.
If you haven't already got this software (freeware), download, install, update and run it,
preferably in safe mode and report the findings (it should product a log file).
2.
SUPERantispyware On-Demand only in free version.
3. MalwareBytes Anti-Malware, On-Demand only in free version
http://download.bleepingcomputer.com/malwarebytes/mbam-setup.exe, right click on the link and select Save As or Save File (As depending on your browser), save it to a location where you can find it easily later.
