Need advice on protecting field computers

Hi, everyone, thanks in advance for the help.

I work for a nonprofit and we do language translation projects all over the world, mainly in developing countries. We often distribute computers to our local consultants in these areas in order to use our software (32-bit Windows application).

We often encounter these computers infested with malware. They are almost never connected to the web, but instead by sharing files via usb drives. It has been very difficult for our staff because they need to get a few files off of these computers via USB drive without getting infected themselves.

Most of what we encouter are older malware (vb scripts, autorun stuff, etc.). Not much zero-day at all.

Do you guys have any advice on how we can retrieve files from these computers safely? I've thought of several solutions, but they all have some issue:
1- obviously cleaning the computer before pulling the files off is ideal, but our staff don't have the necessary time or expertise. Also, there isn't an internet connection in most places to ask for help.
2- using a Linux boot disk to retrieve the files without getting infected. Again, the lack of tech knowledge of our staff is the issue. I could script it, but it is still quite a cumbersome solution.
3- allowing the USB drive to be infected but cleaning it by our staff before reading the contents - tried this last trip but the files we needed were infected and deleted by the antimalware tool.

What am I not seeing? What other options do we have? It has to be reasonably user-friendly and usable without an internet connection. Thanks for your help.

 

Thanks. The names of the files/folders on the USB drive are actually quite "gibberish" to English speakers, because they are the name of the language (third world languages, not anything anyone has ever heard of), the the ISO code for the language, then the abbreviation of the translation type. And the file type is a proprietary type that is used with our proprietary software, so I'm guessing the typical AV software is unaware of it.

So I guess all that is a perfect storm for false positives! Eek!

 

We do use some unicode in our documents, but normally we type the filenames without accents and special characters using normal ansi encoding.

Do you have any experience with the USB Vaccine (Panda) or USB Immunizer (Bitdefender) products? They create a tamper-proof autorun on the USB drive to cut down on autorun-enabled malware. Might be useful for this situation.